Name ______________________________ Class __________________ Date __________________
Skills Worksheet
Directed Reading ASection: What Is an
Animal?
ANIMAL CHARACTERISTICS
Write the letter of the correct answer in the space provided.
_____ 1. Which of the following is an animal?
a. a tree
b. a flower
c. a sponge
d. a mushroom
Multicellular Makeup
_____ 2. Why are all animals called “multicellular” organisms?
a. Their cells have cell walls.
b. They have larger cells than plants.
c. They are made up of many cells.
d. Their cells don’t have cell walls.
Organization in Animals
_____ 3. Which of the following is a group of the same type of cells that work
together?
a. organ system
b. organism
c. organ
d. tissue
_____ 4. What are the heart, lungs, and kidneys?
a. organs
b. cells
c. tissues
d. organ systems
_____ 5. Which of the following is a group of organs that work together?
a. tissue
b. organ system
c. heart
d. cell
Underlying content Copyright by Holt, Rinehart and Winston. Additions and changes to the underlying
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Holt California Life Science
1
Introduction to Animals
Name ______________________________ Class __________________ Date __________________
Directed Reading A continued
Body Plans
Match the correct description with the correct term. Write the letter in the space
provided.
a.
b.
c.
d.
_____ 6. a body plan that is organized
around the center
_____ 7. a body plan with two sides
mirroring each other
coelom
bilateral symmetry
asymmetrical
radial symmetry
_____ 8. a body plan with no symmetry
_____ 9. a body cavity that protects several organs
Getting Energy
Write the letter of the correct answer in the space provided.
_____ 10. Which of the following is an organism that eats other organisms?
a. an organ
b. a plant
c. a consumer
d. a coelom
Reproduction
_____ 11. What type of reproduction produces offspring genetically identical to
the parent?
a. sexual reproduction
b. differentiation
c. asexual reproduction
d. fertilization
_____ 12. What are two types of asexual reproduction?
a. budding and fragmentation
b. differentiation and fertilization
c. fragmentation and differentiation
d. sperm and embryo
_____ 13. What is the process by which an egg nucleus joins with a sperm
nucleus?
a. fragmentation
b. differentiation
c. fertilization
d. budding
Underlying content Copyright by Holt, Rinehart and Winston. Additions and changes to the underlying
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Holt California Life Science
2
Introduction to Animals
Name ______________________________ Class __________________ Date __________________
Directed Reading A continued
Development
_____ 14. What is a fertilized egg that has divided into many cells called?
a. a bud
b. a fragment
c. a sperm
d. an embryo
_____ 15. What is the process by which cells develop structures according to their
function?
a. reproduction
b. differentiation
c. fragmentation
d. fertilization
Movement
_____ 16. How does a young sea anenome move to find its food?
a. It drifts in ocean currents.
b. It flys on wings.
c. It walks on tentacles.
d. It rolls on the ocean floor.
_____ 17. What makes most movement in animals possible?
a. red blood cells
b. white blood cells
c. muscle cells
d. cell walls
Maintaining Body Temperature
_____ 18. What is an animal that maintains its own body temperature internally
called?
a. cold blooded
b. endotherm
c. ectotherm
d. exoskeleton
_____ 19. What is an animal whose body temperature changes with the
environment called?
a. human
b. warm blooded
c. ectotherm
d. endotherm
Underlying content Copyright by Holt, Rinehart and Winston. Additions and changes to the underlying
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Holt California Life Science
3
Introduction to Animals
Name ______________________________ Class __________________ Date __________________
Skills Worksheet
Directed Reading A
Section: The Animal Kingdom
ANIMAL DIVERSITY
Write the letter of the correct answer in the space provided.
_____ 1. How many species of animals have scientists identified?
a. 1 million
b. 3 million
c. 5 million
d. 1 billion
_____ 2. Which animal group is the largest?
a. mammals
b. mollusks
c. annelids
d. arthropods
CLASSIFICATION
_____ 3. Which of the following is NOT information scientists use to organize
animals in groups?
a. structure
b. evolutionary relationships
c. personal preference
d. DNA
_____ 4. All animals, except for most chordates, fall into what classification?
a. protists
b. invertebrates
c. rotlfers
d. annelids
INVERTEBRATE CHARACTERISTICS
_____ 5. Which of these body parts is NOT found in invertebrates?
a. muscles
b. heart
c. brain
d. bones
Underlying content Copyright by Holt, Rinehart and Winston. Additions and changes to the underlying
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Holt California Life Science
4
Introduction to Animals
Name ______________________________ Class __________________ Date __________________
Directed Reading A continued
Sponges
_____ 6. What type of body plan does a sponge have?
a. symmetrical
b. bilateral symmetry
c. asymmetrical
d. radial symmetry
_____ 7. How do sponges reproduce?
a. by budding
b. only asexually
c. only sexually
d. by fragmentation and sexually
Cnidarians
Match the correct description with the correct term. Write the letter in the space
provided.
_____ 8. a class of cnidarians
_____ 9. a cup or bell-shaped body form
with tentacles
a.
b.
c.
d.
polyp
medusa
hydrozoan
cnidosyte
_____ 10. a body form that attaches to hard
surfaces at the base of the cup
_____ 11. a specialized stinging cell
Flatworms
Write the letter of the correct answer in the space provided.
_____ 12. Which of the following are the simplest worms?
a. roundworms
b. flatworms
c. annelids
d. cnidarians
_____ 13. What type of body plan does a flatworm have?
a. symmetrical
b. bilateral symmetry
c. asymmetrical
d. radial symmetry
Underlying content Copyright by Holt, Rinehart and Winston. Additions and changes to the underlying
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Holt California Life Science
5
Introduction to Animals
Name ______________________________ Class __________________ Date __________________
Directed Reading A continued
Roundworms
_____ 14. Roundworms are different from flatworms in that they have which of
the following?
a. radial symmetry
b. cell walls
c. cnidosytes
d. a coelom
Mollusks
_____ 15. Which of the following is NOT true about a mantle?
a. It secretes poison.
b. It is in mollusks.
c. It is a specialized tissue.
d. It secretes shells.
_____ 16. What has the muscular foot evolved into in octopuses?
a. mandibles
b. tentacles
c. eyes
d. ears
Annelids
_____ 17. Each annelid has which of the following?
a. male sex organs
b. both male and female sex organs
c. female sex organs
d. no sex organs
Arthropods
_____ 18. What is the most diverse group in the animal kingdom?
a. mollusks
b. arthropods
c. annelids
d. echinoderms
_____ 19. What is the strong, external armor of an arthropod called?
a. exoskeleton
b. endoskeleton
c. mantle
d. segment
Underlying content Copyright by Holt, Rinehart and Winston. Additions and changes to the underlying
content are the responsibility of the instructor.
Holt California Life Science
6
Introduction to Animals
Name ______________________________ Class __________________ Date __________________
Directed Reading A continued
Echinoderms
_____ 20. Echinoderms have which of the following body plans?
a. radial symmetry as larvae; bilateral symmetry as adults
b. radial symmetry as larvae and adults
c. bilateral symmetry as larvae and adults
d. bilateral symmetry as larvae; radial symmetry as adults
_____ 21. A sea star that regenerates a whole individual from a severed arm uses
what type of reproduction?
a. sexual
b. budding
c. asexual
d. fertilization
VERTEBRATE CHARACTERISTICS
_____ 22. What is a stiff but flexible rod that supports the body of a chordate?
a. spine
b. notochord
c. backbone
d. vertebrae
_____ 23. What is an animal with a backbone called?
a. echinoderm
b. invertebrate
c. vertebrate
d. arthropod
_____ 24. What is a strong but flexible column of individual bony units, or
vertebrae?
a. backbone
b. mantle
c. spinal cord
d. notochord
_____ 25. What is an internal skeleton made of bone and cartilage?
a. mantle
b. endoskeleton
c. exoskeleton
d. shell
_____ 26. What are the five main groups of vertebrates?
a. insects, worms, birds, fish, mammals
b. mollusks, annelids, sea urchins, snakes, humans
c. fish, amphibians, reptiles, birds, mammals
d. insects, reptiles, birds, mammals, humans
Underlying content Copyright by Holt, Rinehart and Winston. Additions and changes to the underlying
content are the responsibility of the instructor.
Holt California Life Science
7
Introduction to Animals
Name ______________________________ Class __________________ Date __________________
Directed Reading A continued
Fish
Match the correct description with the correct term. Write the letter in the space
provided.
_____ 27. have a skeleton made of flexible
tissue
a. bony fish
b. cartilaginous fish
_____ 28. have a bony skeleton
Amphibians
Write the letter of the correct answer in the space provided.
_____ 29. Why do most amphibians live near fresh water?
a. Their eggs and larvae need water to survive.
b. They breathe through gills.
c. They are dry skinned and need water.
d. It is the only place to find food.
_____ 30. What are tropical amphibians that live under logs and in burrows?
a. frogs
b. tadpoles
c. caecilians
d. salamanders
Reptiles
_____ 31. Which of the following is a reason why most reptiles live on land?
a. They cannot swim.
b. Their skin must be kept dry.
c. They do not need water to lay their eggs.
d. They all eat other vertebrates.
Birds
_____ 32. Which of the following characteristics is only found in birds?
a. They have the ability to fly.
b. They have feathers.
c. They are endothermic.
d. They reproduce by sexual reproduction.
_____ 33. Which bird uses its wings to swim?
a. the penguin
b. the emu
c. the duck
d. the ostrich
Underlying content Copyright by Holt, Rinehart and Winston. Additions and changes to the underlying
content are the responsibility of the instructor.
Holt California Life Science
8
Introduction to Animals
Name ______________________________ Class __________________ Date __________________
Directed Reading A continued
Mammals
Match the correct description with the correct term. Write the letter in the space
provided.
_____ 34. a mammal that lays shelled eggs
_____ 35. a mammal with offspring that
finish developing in the
mother’s pouch
a. placental
b. marsupial
c. monotreme
_____ 36. a mammal with an organ that
exchanges wastes and nutrients
with developing offspring
Underlying content Copyright by Holt, Rinehart and Winston. Additions and changes to the underlying
content are the responsibility of the instructor.
Holt California Life Science
9
Introduction to Animals
Name ______________________________ Class __________________ Date __________________
Skills Worksheet
Directed Reading A
Section: Invertebrates
INVERTEBRATE CHARACTERISTICS
Write the letter of the correct answer in the space provided.
_____ 1. What makes all invertebrates similar?
a. They eat food through their mouths.
b. They live in water.
c. They do not have backbones.
d. They are similar in shape.
Body Symmetry
Match the correct description with the correct term. Write the letter in the space
provided.
_____ 2. Many lines can be drawn
through the center of the body.
_____ 3. Two sides of the body mirror
each other.
a. radial symmetry
b. bilateral symmetry
c. asymmetrical
_____ 4. This describes an irregular
shape.
Segmentation
Write the letter of the correct answer in the space provided.
_____ 5. Which of the following is part of a larger structure set off by
boundaries?
a. head
b. thorax
c. body
d. segment
Support of the Body
_____ 6. What kind of body support does a lobster have?
a. thick skin
b. glassy structures
c. an exoskeleton
d. an endoskeleton
Underlying content Copyright by Holt, Rinehart and Winston. Additions and changes to the underlying
content are the responsibility of the instructor.
Holt California Life Science
10
Introduction to Animals
Name ______________________________ Class __________________ Date __________________
Directed Reading A continued
Respiratory and Circulatory Systems
Match the correct description with the correct term. Write the letter in the space
provided.
_____ 7. a system that takes in oxygen
and releases carbon dioxide
_____ 8. a network of tubes inside insect
bodies that performs respiration
a. circulatory system
b. respiratory system
c. tracheae
_____ 9. a system that moves oxygen,
carbon dioxide, and nutrients through the body
Match the correct description with the correct term. Write the letter in the space
provided.
a. open circulatory
_____ 10. a fluid that carries substances
through the body
system
b. closed circulatory
_____ 11. a system in which blood moves
through open spaces
system
c. blood
_____ 12. a system in which blood moves
through closed loops
Digestive and Excretory Systems
Match the correct description with the correct term. Write the letter in the space
provided.
_____ 13. This system provides energy for
animals by digesting their food.
_____ 14. The mouth and anus form two
ends of this tube.
a. digestive tract
b. digestive system
c. excretory system
_____ 15. This system eliminates waste and extra water from cells.
Nervous Systems
Match the correct description with the correct term. Write the letter in the space
provided.
a. sense organ
b. brain
c. nervous system
_____ 16. receives and sends electrical
signals that control all body
functions
_____ 17. acts as the body’s control center
_____ 18. collects information from outside the body
Underlying content Copyright by Holt, Rinehart and Winston. Additions and changes to the underlying
content are the responsibility of the instructor.
Holt California Life Science
11
Introduction to Animals
Name ______________________________ Class __________________ Date __________________
Directed Reading A continued
Reproduction and Development
Match the correct description with the correct term. Write the letter in the space
provided.
_____
19.A part of the parent organism
develops into a new organism,
pinches off, and lives
independently.
a. budding
b. fragmentation
_____ 20. A part of the parent organism breaks off and develops into an identical
organism.
Complete Metamorphosis
Match the correct description with the correct term. Write the letter in the space
provided.
_____ 21. a life cycle process in which a
rapid change from immature to
adult organism takes place
a. metamorphosis
b. complete
metamorphosis
_____ 22. a complex life cycle change that
includes egg, larva, pupa, and adult stages
Incomplete Metamorphosis
Write the letter of the correct answer in the space provided.
_____ 23. What are the stages of incomplete metamorphosis?
a. egg, larva, pupa, adult
b. larva, pupa, adult
c. egg, nymph, adult
d. pupa, nymph, adult
_____ 24. What is the process in which some insects shed their exoskeletons as
they grow?
a. molting
b. shedding
c. peeling
d. warping
Underlying content Copyright by Holt, Rinehart and Winston. Additions and changes to the underlying
content are the responsibility of the instructor.
Holt California Life Science
12
Introduction to Animals
Name ______________________________ Class __________________ Date __________________
Skills Worksheet
Directed Reading A
Section: Vertebrates
VERTEBRATE CHARACTERISTICS
Write the letter of the correct answer in the space provided.
_____ 1. Which of the following features is found only in vertebrates?
a. head
b. protein
c. tissue
d. backbone
_____ 2. Which of the following is a flexible and strong connective tissue?
a. cartilage
b. bone
c. skull
d. vertebrae
Body Symmetry
Match the correct description with the correct term. Write the letter in the space
provided.
a.
b.
c.
d.
_____ 3. the back
_____ 4. the belly
_____ 5. the head
dorsal
anterior
posterior
ventral
_____ 6. the tail
Body Coverings
Match the correct description with the correct term. Write the letter in the space
provided.
a.
b.
c.
d.
_____ 7. body covering of fish and
reptiles
_____ 8. slippery fluid that covers
amphibians and fish
feathers
fur and hair
scales
mucous
_____ 9. body covering that keeps body
temperature stable in birds
_____ 10. body covering that keeps body temperature stable in mammals
Underlying content Copyright by Holt, Rinehart and Winston. Additions and changes to the underlying
content are the responsibility of the instructor.
Holt California Life Science
13
Introduction to Animals
Name ______________________________ Class __________________ Date __________________
Directed Reading A continued
Support of the Body
Match the correct description with the correct term. Write the letter in the space
provided.
_____ 11. surrounds and protects the brain
_____ 12. surrounds and protects the spinal
cord
a. backbone
b. limb bone
c. skull
_____ 13. provides a place for muscle
tissue to attach
Respiratory Systems
Write the letter of the correct answer in the space provided.
_____ 14. What is the main respiratory organ in fish?
a. lungs
b. bloodstream
c. gills
d. scales
_____ 15. Why are the main respiratory organs of land vertebrates inside the
body?
a. to keep them clean
b. to keep them from drying out
c. to protect them from infection
d. to provide body support
_____ 16. What is the main respiratory organ of a frog?
a. mucous
b. circulatory system
c. gills
d. lungs
Circulatory Systems
_____ 17. What pushes blood through the closed circulatory system of a
vertebrate?
a. lungs
b. heart
c. blood vessels
d. arteries
_____ 18. Which of the following are the blood vessels that carry blood to and
from the heart?
a. arteries; veins
b. veins; capillaries
c. capillaries; veins
d. veins; arteries
Underlying content Copyright by Holt, Rinehart and Winston. Additions and changes to the underlying
content are the responsibility of the instructor.
Holt California Life Science
14
Introduction to Animals
Name ______________________________ Class __________________ Date __________________
Directed Reading A continued
_____ 19. Where does oxygen move into the blood of land vertebrates?
a. in the heart
b. in the veins
c. in the brain
d. in the gills or lungs
Digestive and Excretory Systems
Match the correct description with the correct term. Write the letter in the space
provided.
_____ 20. the long tube of the digestive
system
_____ 21. the organ that breaks down food
and absorbs nutrients
a.
b.
c.
d.
small intestine
digestive tract
large intestine
kidneys
_____ 22. the organ that turns waste into
feces
_____ 23. the organ that filters urea from
the blood
Nervous Systems
Write the letter of the correct answer in the space provided.
_____ 24. What happens when sound reaches the ear?
a. The ear interprets the sound waves.
b. The ear sends impulses through sensory nerves to the brain.
c. The ear sends sound waves through the circulatory system.
d. The ear blocks the sound waves to protect the brain.
_____ 25. Which of the following carry command impulses from the brain?
a. arteries
b. sensory nerves
c. veins
d. motor nerves
Reproduction and Development
_____ 26. How do most vertebrates reproduce?
a. sexual reproduction
b. asexual reproduction
c. budding
d. fragmentation
_____ 27. What process takes place in an embryo’s cells as it develops?
a. fusion
b. fertilization
c. differentiation
d. metamorphosis
Underlying content Copyright by Holt, Rinehart and Winston. Additions and changes to the underlying
content are the responsibility of the instructor.
Holt California Life Science
15
Introduction to Animals
Name ______________________________ Class __________________ Date __________________
Directed Reading A continued
_____ 28. Which of the following is NOT true of fish and amphibian larvae?
a. They hatch in water.
b. They can reproduce.
c. They can’t reproduce.
d. They live on their own.
_____ 29. Which of the following animals have a larval stage in their life cycle?
a. reptiles
b. amphibians
c. birds
d. mammals
Parental Care
_____ 30. How do parenting skills of birds and mammals differ from those of fish
and reptiles?
a. Birds and mammals have more offspring, so they parent longer.
b. Birds and mammals have fewer offspring, so they parent longer.
c. Only fish and reptiles parent until their offspring are adults.
d. Only birds and mammals abandon their offspring at birth.
Underlying content Copyright by Holt, Rinehart and Winston. Additions and changes to the underlying
content are the responsibility of the instructor.
Holt California Life Science
16
Introduction to Animals
Name ______________________________ Class __________________ Date __________________
Skills Worksheet
Directed Reading B
Section: What Is an Animal?
ANIMAL CHARACTERISTICS
_____ 1. Until about 200 years ago, people thought sponges were
a. vertebrates.
c. plants.
b. fungi.
d. animals.
_____ 2. How do animal cells differ from plant cells?
a. They are larger than plant cells.
b. Animal cells have cell walls; plant cells do not.
c. They are made up of different chemical components.
d. Animal cells are surrounded only by cell membranes.
_____ 3. All animals are
a. single celled.
b. covered in fur.
c. made up of many cells.
d. asexual.
_____ 4. Groups of the same type of cells that work together to perform a
specific function are
a. organ systems.
b. organs.
c. muscles.
d. tissues.
_____ 5. Into which of the following categories do the heart, lungs, and kidneys
fall?
a. organs
b. multicellular organisms
c. tissues
d. organ systems
_____ 6. An organ system is a
a. group of tissues that perform a specific function.
b. single tissue that performs several functions.
c. group of organs that perform a specific function.
d. single organ that performs a specific function.
_____ 7. A coelom is
a. a structure found only in plants.
b. a structure found inside an organ.
c. a body cavity that protects many organs.
d. an exoskeleton.
Underlying content Copyright by Holt, Rinehart and Winston. Additions and changes to the underlying
content are the responsibility of the instructor.
Holt California Life Science
17
Introduction to Animals
Name ______________________________ Class __________________ Date __________________
Directed Reading B continued
_____ 8. A sea star
a. has bilateral symmetry.
b. has radial symmetry.
c. has biradial symmetry.
d. is asymmetrical.
_____ 9. When an animal’s two sides mirror each other, it
a. has bilateral symmetry.
b. has radial symmetry.
c. has biradial symmetry.
d. is asymmetrical.
_____ 10. An organism that feeds on other organisms to meet its energy needs is
called a
a. consumer.
b. producer.
c. plant
d. customer.
_____ 11. For food, mosquitoes
a. drink nectar.
b. drink blood.
c. eat animals.
d. photosynthesize sunlight.
_____ 12. The type of reproduction that results in offspring genetically identical
to the parent is called
a. sexual reproduction.
b. differentiation.
c. asexual reproduction.
d. fertilization.
_____ 13. Two types of asexual reproduction are
a. budding and fragmentation.
b. differentiation and fertilization.
c. egg and differentiation.
d. sperm and embryo.
_____ 14. The process of an egg’s nucleus joining with a sperm’s nucleus is
called
a. budding.
b. differentiation.
c. fragmentation.
d. fertilization.
Underlying content Copyright by Holt, Rinehart and Winston. Additions and changes to the underlying
content are the responsibility of the instructor.
Holt California Life Science
18
Introduction to Animals
Name ______________________________ Class __________________ Date __________________
Directed Reading B continued
_____ 15. What is the process by which cells develop structures according to their
function?
a. reproduction
b. differentiation
c. fragmentation
d. fertilization
_____ 16. Which of the following is an example of an animal that can move from
one place to another at only one stage of its life?
a. caterpillar
b. anemone
c. parrot
d. nautilus
_____ 17. An animal that maintains its own body temperature is called a(n)
a. endotemp.
b. endotherm.
c. ectotherm.
d. exotherm.
_____ 18. An animal whose body temperature changes with the environment is
called a(n)
a. endotemp.
b. endotherm.
c. ectotherm.
d. exotherm.
19. What are three reasons why animals move?
_______________________________________________________________
_______________________________________________________________
_______________________________________________________________
20. What makes most movement in animals possible?
_______________________________________________________________
_______________________________________________________________
_______________________________________________________________
21. How do birds and mammals maintain their body heat?
_______________________________________________________________
_______________________________________________________________
_______________________________________________________________
Underlying content Copyright by Holt, Rinehart and Winston. Additions and changes to the underlying
content are the responsibility of the instructor.
Holt California Life Science
19
Introduction to Animals
Name ______________________________ Class __________________ Date __________________
Skills Worksheet
Directed Reading B
Section: The Animal Kingdom
ANIMAL DIVERSITY
_____ 1. Scientists have identified
a. over 1 million species of animals.
b. over 3 million species of animals.
c. over 5 million species of animals.
d. over 1 billion species of animals.
CLASSIFICATION
_____ 2. Scientists do NOT organize animals into groups based on
a. structure.
b. personal preference.
c. evolutionary relationships.
d. DNA.
_____ 3. All animals, except chordates, fall into what classification?
a. amphibians
b. invertebrates
c. mammals
d. annelids
INVERTEBRATE CHARACTERISTICS
_____ 4. Which of these body parts is NOT characteristic of invertebrates?
a. muscles
b. hair
c. brain
d. bones
_____ 5. What are the many tubes and thousands of small holes of a sponge?
a. eyes
b. pores
c. a jelly-like material
d. glassy structures
_____ 6. The sponge’s body plan
a. has radial symmetry.
b. has bilateral symmetry.
c. is symmetrical.
d. is asymmetrical.
Underlying content Copyright by Holt, Rinehart and Winston. Additions and changes to the underlying
content are the responsibility of the instructor.
Holt California Life Science
20
Introduction to Animals
Name ______________________________ Class __________________ Date __________________
Directed Reading B continued
_____ 7. Unlike flatworms, roundworms have a(n)
a. coelom.
b. endoskeleton.
c. exoskeleton.
d. mantle.
_____ 8. The body plan of an annelid
a. is asymmetrical.
b. has bilateral symmetry.
c. has radial symmetry.
d. has biradial symmetry.
_____ 9. Annelids are also called
a. segmented worms.
b. detached worms.
c. vertebrate worms.
d. smooth worms.
_____ 10. Which of the following are NOT arthropods?
a. crabs
b. shrimp
c. spiders
d. leeches
_____ 11. Which of the following are NOT echinoderms?
a. crabs
b. sea stars
c. sea urchins
d. sand dollars
12. Why have scientists placed animals they have discovered into groups smaller
than species for identification?
_______________________________________________________________
_______________________________________________________________
_______________________________________________________________
13. What are the three major classes of cnidarians?
_______________________________________________________________
_______________________________________________________________
_______________________________________________________________
Underlying content Copyright by Holt, Rinehart and Winston. Additions and changes to the underlying
content are the responsibility of the instructor.
Holt California Life Science
21
Introduction to Animals
Name ______________________________ Class __________________ Date __________________
Directed Reading B continued
14. What are the cnidarian’s two types of body plan?
_______________________________________________________________
_______________________________________________________________
15. Describe how the body forms of sea anemones and coral are different in the
larval and adult stages.
_______________________________________________________________
_______________________________________________________________
_______________________________________________________________
16. What is a parasite?
_______________________________________________________________
_______________________________________________________________
17. In what two ways do flatworms reproduce?
_______________________________________________________________
_______________________________________________________________
Match the correct description with the correct term. Write the letter in the space
provided.
_____ 18. secretes the shells of mollusks
_____ 19. is used to move
20. What are two benefits of an arthropod’s exoskeleton?
a. muscular foot
b. mantle
_______________________________________________________________
_______________________________________________________________
21. What are four purposes of an echinoderm’s water vascular system?
_______________________________________________________________
_______________________________________________________________
_______________________________________________________________
_______________________________________________________________
Underlying content Copyright by Holt, Rinehart and Winston. Additions and changes to the underlying
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Holt California Life Science
22
Introduction to Animals
Name ______________________________ Class __________________ Date __________________
Directed Reading B continued
22. What is the process by which echinoderms reproduce sexually?
_______________________________________________________________
_______________________________________________________________
_______________________________________________________________
VERTEBRATE CHARACTERISTICS
_____ 23. All chordates have a(n)
a. backbone.
b. exoskeleton.
c. notochord.
d. radially symmetrical body plan.
_____ 24. A stiff but flexible rod that supports the body of an animal is called
a(n)
a. spine.
b. notochord.
c. backbone.
d. vertebrae.
_____ 25. A strong but flexible column of individual bony units, or vertebrae, is
called a(n)
a. backbone.
b. nervous system.
c. spinal cord.
d. notochord.
_____ 26. What is an internal skeleton that is made of bone and cartilage?
a. backbone
b. endoskeleton
c. exoskeleton
d. shell
_____ 27. The five main groups of vertebrates are
a. insects, worms, birds, fish, mammals.
b. mollusks, annelids, sea urchins, snakes, humans.
c. fish, amphibians, reptiles, birds, mammals.
d. insects, reptiles, birds, mammals, humans.
_____ 28. Most amphibians live near freshwater because
a. their eggs and larvae need water to survive.
b. they breathe through gills.
c. they are dry skinned and need water.
d. it is the only place to find food.
Underlying content Copyright by Holt, Rinehart and Winston. Additions and changes to the underlying
content are the responsibility of the instructor.
Holt California Life Science
23
Introduction to Animals
Name ______________________________ Class __________________ Date __________________
Directed Reading B continued
_____ 29. Most reptiles live on land because
a. they cannot swim.
b. their skin must be kept dry.
c. they do not need water to lay their eggs.
d. they all eat other vertebrates.
_____ 30. Which of the following birds uses its wings to swim?
a. emu
b. ostrich
c. goose
d. penguin
_____ 31. Which of the following birds runs instead of flying?
a. emu
b. parakeet
c. goose
d. penguin
32. How are lancelets different from vertebrates?
_______________________________________________________________
_______________________________________________________________
_______________________________________________________________
Match the correct description with the correct term. Write the letter in the space
provided.
_____ 33. group that includes sharks and
stingrays
a. bony fish
b. cartilaginous fish
_____ 34. the largest group of fish
35. What are two characteristics shared by all mammals.
_______________________________________________________________
_______________________________________________________________
Match the correct description with the correct term. Write the letter in the space
provided.
_____ 36. Offspring develop in shelled eggs.
_____ 37. Offspring develop in a placenta.
a. placental mammal
b. marsupial
c. monotreme
_____ 38. Offspring develop in the mother’s
pouch.
Underlying content Copyright by Holt, Rinehart and Winston. Additions and changes to the underlying
content are the responsibility of the instructor.
Holt California Life Science
24
Introduction to Animals
Name ______________________________ Class __________________ Date __________________
Skills Worksheet
Directed Reading B
Section: Invertebrates
INVERTEBRATE CHARACTERISTICS
_____ 1. All invertebrates
a. absorb nutrients through tissue.
b. live in water.
c. lack backbones.
d. are similar in shape.
_____ 2. Which of the following is NOT a segment of an insect?
a. head
b. thorax
c. abdomen
d. tail
_____ 3. Which of the following is NOT a body support for an invertebrate?
a. glassy structures
b. a backbone
c. an exoskeleton
d. thick skin
_____ 4. Which of the following performs respiration in lobsters?
a. lungs
b. gills
c. tracheae
d. blood
_____ 5. Blood moves through open spaces in the body in a(n)
a. open circulatory system.
b. closed circulatory system.
c. open respiratory system.
d. closed respiratory system.
_____ 6. An animal digests food in its
a. circulatory system.
b. digestive system.
c. respiratory system.
d. nervous system.
_____ 7. Which of the following acts as the control center for the nervous
system of many animals?
a. sense organs
b. nerve
c. nerve cord
d. brain
Underlying content Copyright by Holt, Rinehart and Winston. Additions and changes to the underlying
content are the responsibility of the instructor.
Holt California Life Science
25
Introduction to Animals
Name ______________________________ Class __________________ Date __________________
Directed Reading B continued
_____ 8. Which of the following collects information from outside the body?
a. sense organs
b. nerve
c. nerve cord
d. brain
_____ 9. Which of the following is a form of reproduction in which a part of the
parent organism develops and pinches off to live independently?
a. budding
b. fragmentation
c. sexual
d. fertilization
_____ 10. Which of the following is a form of reproduction in which a part of an
organism breaks off and develops into an identical individual?
a. budding
b. fragmentation
c. sexual
d. fertilization
_____ 11. The process in which some insects shed their exoskeletons as they
grow is called
a. molting.
b. shedding.
c. peeling.
d. warping.
12. Identify three ways in which invertebrates have adapted to their environments.
_______________________________________________________________
_______________________________________________________________
_______________________________________________________________
13. A sponge has an ______________________ body plan.
14. A sea hare’s body plan has ______________________ symmetry.
15. A jellyfish’s body plan has ______________________ symmetry.
16. Insects have ______________________ to protect their inner body parts.
17. Animals take in oxygen and release carbon dioxide through
______________________.
18. Some invertebrates have a separate ______________________ system to
eliminate excess water and wastes from cells.
Underlying content Copyright by Holt, Rinehart and Winston. Additions and changes to the underlying
content are the responsibility of the instructor.
Holt California Life Science
26
Introduction to Animals
Name ______________________________ Class __________________ Date __________________
Directed Reading B continued
19. List the parts of the digestive system of the snail.
_______________________________________________________________
_______________________________________________________________
_______________________________________________________________
_______________________________________________________________
20. What are the four stages of complete metamorphosis?
_______________________________________________________________
_______________________________________________________________
_______________________________________________________________
_______________________________________________________________
21. What are the three stages of incomplete metamorphosis?
_______________________________________________________________
_______________________________________________________________
_______________________________________________________________
Underlying content Copyright by Holt, Rinehart and Winston. Additions and changes to the underlying
content are the responsibility of the instructor.
Holt California Life Science
27
Introduction to Animals
Name ______________________________ Class __________________ Date __________________
Skills Worksheet
Directed Reading B
Section: Vertebrates
VERTEBRATE CHARACTERISTICS
_____ 1. Only vertebrates have
a. a head.
b. protein.
c. tissue.
d. a backbone.
_____ 2. The flexible and strong connective tissue found only in vertebrates is
called
a. cartilage.
b. bone.
c. skull.
d. hard tissue.
_____ 3. The back of a vertebrate is the
a. dorsal side.
b. ventral side.
c. anterior.
d. posterior.
_____ 4. The head of a vertebrate is the
a. dorsal side.
b. ventral side.
c. anterior.
d. posterior.
_____ 5. Which of the following helps keep a mammal’s body temperature
stable?
a. feathers
b. fur and hair
c. scales
d. mucus
_____ 6. Which of the following helps keep a bird’s body temperature stable?
a. feathers
b. fur and hair
c. scales
d. mucus
Underlying content Copyright by Holt, Rinehart and Winston. Additions and changes to the underlying
content are the responsibility of the instructor.
Holt California Life Science
28
Introduction to Animals
Name ______________________________ Class __________________ Date __________________
Directed Reading B continued
_____ 7. Which of the following is NOT one of the three main parts of an
endoskeleton?
a. backbone
b. skull
c. mantle
d. limb bones
_____ 8. The main respiratory organs of a fish are the
a. lungs.
b. arteries.
c. gills.
d. scales.
_____ 9. The main respiratory organs of land vertebrates are inside the body to
a. keep them clean
b. keep them from drying out.
c. protect them from infection.
d. provide body support.
_____ 10. The main respiratory organs of a frog are the
a. arteries.
b. scales.
c. gills.
d. lungs.
_____ 11. In vertebrates, blood is pushed through a closed circulatory system by
the
a. lungs.
b. heart.
c. blood vessels.
d. arteries.
_____ 12. The blood vessels that carry blood to and from the heart are
a. arteries and veins.
b. veins and capillaries.
c. capillaries and veins.
d. arteries and capillaries.
_____ 13. The main blood vessels are connected by a network of
a. arteries.
b. veins.
c. capillaries.
d. pumps.
Underlying content Copyright by Holt, Rinehart and Winston. Additions and changes to the underlying
content are the responsibility of the instructor.
Holt California Life Science
29
Introduction to Animals
Name ______________________________ Class __________________ Date __________________
Directed Reading B continued
_____ 14. The organ in which most food breakdown occurs and nutrients are
absorbed is the
a. small intestine.
b. large intestine.
c. kidney.
d. anus.
_____ 15. The organ that filters urea from the blood is the
a. small intestine.
b. large intestine.
c. kidney.
d. anus.
_____ 16. The organ that turns waste into feces is the
a. small intestine.
b. large intestine.
c. kidney.
d. anus.
_____ 17. When sound reaches the ear,
a. the ear interprets the sound waves.
b. the ear sends impulses through sensory nerves to the brain.
c. the ear sends sound waves through the circulatory system.
d. the ear blocks the sound waves to protect the brain.
_____ 18. Command impulses are carried from the brain by
a. arteries.
b. sensory nerves.
c. veins.
d. motor nerves.
_____ 19. Almost all vertebrates reproduce through
a. sexual reproduction.
b. asexual reproduction.
c. budding.
d. fragmentation.
_____ 20. An embryo develops specialized cells through
a. fusion.
b. fertilization.
c. differentiation.
d. metamorphosis.
_____ 21. Fish and amphibian larvae
a. hatch on land.
b. can reproduce.
c. can’t reproduce.
d. are exactly the same as adults.
Underlying content Copyright by Holt, Rinehart and Winston. Additions and changes to the underlying
content are the responsibility of the instructor.
Holt California Life Science
30
Introduction to Animals
Name ______________________________ Class __________________ Date __________________
Directed Reading B continued
_____ 22. Animals that have a larval stage in their life cycle include
a. reptiles.
b. amphibians.
c. birds.
d. mammals.
_____ 23. Parenting skills of birds and mammals differ from those of fish and
reptiles in that
a. fish and reptiles parent until their offspring are adults.
b. birds and mammals have fewer offspring, so they parent longer.
c. fish and reptiles have fewer offspring, so they parent longer.
d. only birds and mammals abandon their offspring at birth.
24. What happens to the cartilage of most vertebrate embryos as they grow?
_______________________________________________________________
_______________________________________________________________
25. What unique purpose is served by the mucous covering on the bodies of
amphibians?
_______________________________________________________________
_______________________________________________________________
26. How does the respiratory system in fish work?
_______________________________________________________________
_______________________________________________________________
_______________________________________________________________
27. Describe how the circulatory system and respiratory system in a land
vertebrate work together.
_______________________________________________________________
_______________________________________________________________
_______________________________________________________________
_______________________________________________________________
_______________________________________________________________
28. How do animals with larger brains differ from those with smaller brains?
_______________________________________________________________
_______________________________________________________________
_______________________________________________________________
Underlying content Copyright by Holt, Rinehart and Winston. Additions and changes to the underlying
content are the responsibility of the instructor.
Holt California Life Science
31
Introduction to Animals
Name ______________________________ Class __________________ Date __________________
Skills Worksheet
Vocabulary and Section Summary A
What Is an Animal?
VOCABULARY
In your own words, write a definition of the following terms in the space provided.
1. coelom
_______________________________________________________________
_______________________________________________________________
_______________________________________________________________
2. consumer
_______________________________________________________________
_______________________________________________________________
_______________________________________________________________
3. differentiation
_______________________________________________________________
_______________________________________________________________
_______________________________________________________________
SECTION SUMMARY
Read the following section summary.
• All animals are multicellular organisms. Specialized cells in animals are
organized into tissues, organs, and organ systems.
• Most animals have bilateral symmetry or radial symmetry. Some are
asymmetrical.
• Animals consume other organisms to get energy.
• Animals reproduce asexually or sexually.
• As an embryo develops, its cells differentiate.
• Animals move in many ways.
• Animals that maintain their own body temperature are endotherms. Animals that
rely on their environment to maintain their body temperature are ectotherms.
Underlying content Copyright by Holt, Rinehart and Winston. Additions and changes to the underlying
content are the responsibility of the instructor.
Holt California Life Science
32
Introduction to Animals
Name ______________________________ Class __________________ Date __________________
Skills Worksheet
Vocabulary and Section Summary A
The Animal Kingdom
VOCABULARY
In your own words, write a definition of the following terms in the space provided.
1. invertebrate
_______________________________________________________________
_______________________________________________________________
2. exoskeleton
_______________________________________________________________
_______________________________________________________________
3. vertebrate
_______________________________________________________________
_______________________________________________________________
4. endoskeleton
_______________________________________________________________
_______________________________________________________________
SECTION SUMMARY
Read the following section summary.
• The animal kingdom can be divided into two main groups: invertebrates and
vertebrates. Invertebrates do not have backbones. Vertebrates have backbones.
• Sponges, cnidarians, flatworms, roundworms, mollusks, annelids, arthropods,
and echinoderms are groups of invertebrates.
• Fish, amphibians, reptiles, birds, and mammals are groups of vertebrates.
• Invertebrate bodies can be asymmetrical, radially symmetrical, or bilaterally
symmetrical. Some invertebrates have different body symmetries at different
stages in their life cycle.
• Most vertebrate bodies have bilateral symmetry.
• Many invertebrates reproduce by asexual reproduction and sexual reproduction.
Most vertebrates reproduce only by sexual reproduction.
Underlying content Copyright by Holt, Rinehart and Winston. Additions and changes to the underlying
content are the responsibility of the instructor.
Holt California Life Science
33
Introduction to Animals
Name ______________________________ Class __________________ Date __________________
Skills Worksheet
Vocabulary and Section Summary A
Invertebrates
VOCABULARY
In your own words, write a definition of the following terms in the space provided.
1. segment
_______________________________________________________________
_______________________________________________________________
2. open circulatory system
_______________________________________________________________
_______________________________________________________________
3. closed circulatory system
_______________________________________________________________
_______________________________________________________________
4. metamorphosis
_______________________________________________________________
_______________________________________________________________
SECTION SUMMARY
Read the following section summary.
• Invertebrate bodies are asymmetrical, have radial symmetry, or bilateral
symmetry.
• The bodies of many invertebrates are divided into segments.
• Invertebrates have protective outer coverings that provide support and serve as a
place for muscles to attach.
• Invertebrates may have many basic organ systems, such as a respiratory
system, a circulatory system, a digestive system, an excretory system, a nervous
system, and a reproductive system.
• Invertebrates reproduce asexually and sexually. Invertebrates develop from
embryos into larvae and from larvae into adults.
Underlying content Copyright by Holt, Rinehart and Winston. Additions and changes to the underlying
content are the responsibility of the instructor.
Holt California Life Science
34
Introduction to Animals
Name ______________________________ Class __________________ Date __________________
Skills Worksheet
Vocabulary and Section Summary A
Vertebrates
VOCABULARY
In your own words, write a definition of the following terms in the space provided.
1. cartilage
_______________________________________________________________
_______________________________________________________________
_______________________________________________________________
2. small intestine
_______________________________________________________________
_______________________________________________________________
_______________________________________________________________
3. large intestine
_______________________________________________________________
_______________________________________________________________
_______________________________________________________________
SECTION SUMMARY
Read the following section summary.
• Skin protects the body from the environment. Skin of vertebrates may be
covered in scales, feathers, or fur.
• Most vertebrates have an endoskeleton made of bone. The endoskeleton
provides support, protection, and a place for muscles to attach.
• Major organ systems of vertebrates are the respiratory system, circulatory
system, digestive system, excretory system, nervous system, and reproductive
system.
• Cells of embryos differentiate and specialize as the embryo develops.
• The amount of parental care given to offspring varies among species of
vertebrates.
Underlying content Copyright by Holt, Rinehart and Winston. Additions and changes to the underlying
content are the responsibility of the instructor.
Holt California Life Science
35
Introduction to Animals
Name ______________________________ Class __________________ Date __________________
Skills Worksheet
Vocabulary and Section Summary B
What Is an Animal?
VOCABULARY
After you finish reading the section, try this puzzle! Use the clues below to solve
the crossword puzzle on the following page.
ACROSS
1. Animals called
______________________
rely on their environment to
maintain their body
temperature.
8. ______________________
are birds and mammals that
maintain their own body
temperatures by using some
of the energy released by
chemical reactions.
9. Reproduction in which parts
of an organism break off and
then develop into new
individuals is known as
______________________.
11. A body cavity or
______________________
contains the internal organs
of some organisms.
DOWN
2.______________________ occurs when sex
cells from two parents combine to form
offspring.
3.A(n) ______________________ is a group of
organs that work together to perform a specific
function.
4.An organism that is
______________________ is made up of many
cells.
5.An organism that eats other organisms or
organic matter is a(n)
______________________.
6.In the process of ______________________,
the structure and function of the parts of an
organism change to enable specialization of
those parts.
7.An organism that is a(n)
______________________ is in one of the early
stages of development.
10.When an organism reproduces by
______________________, one of its parts
develops into a new organism.
Underlying content Copyright by Holt, Rinehart and Winston. Additions and changes to the underlying
content are the responsibility of the instructor.
Holt California Life Science
36
Introduction to Animals
Name ______________________________ Class __________________ Date __________________
Vocabulary and Section Summary B continued
SECTION SUMMARY
Read the following section summary.
• All animals are multicellular organisms. Specialized cells in animals are
organized into tissues, organs, and organ systems.
• Most animals have bilateral symmetry or radial symmetry. Some are
asymmetrical.
• Animals consume other organisms to get energy.
• Animals reproduce asexually or sexually.
• As an embryo develops, its cells differentiate.
• Animals move in many ways.
• Animals that maintain their own body temperature are endotherms. Animals that
rely on their environment to maintain their body temperature are ectotherms.
Underlying content Copyright by Holt, Rinehart and Winston. Additions and changes to the underlying
content are the responsibility of the instructor.
Holt California Life Science
37
Introduction to Animals
Name ______________________________ Class __________________ Date __________________
Skills Worksheet
Vocabulary and Section Summary B
The Animal Kingdom
VOCABULARY
After you finish reading the section, try this puzzle! In the space provided, write
the term described. Then, find the words in the word search puzzle on the next
page. Terms can be hidden in the puzzle vertically, horizontally, diagonally, or
backward.
_____________________ 1. an animal that does not have a backbone
_____________________ 2. a hard, external, supporting structure for an
animal
_____________________ 3. an animal that has a backbone
_____________________ 4. an internal skeleton made of bone and cartilage
_____________________ 5. small holes in the body of a sponge
_____________________ 6. a cup or bell-shaped body that has tentacles
extending from it
_____________________ 7. a specialized tissue that secretes the shell of snails,
clams, and oysters
_____________________ 8. a name that means “spiny skinned”
_____________________ 9. a stiff but flexible rod that supports the body of a
chordate
_____________________ 10. individual bony units that make up the backbone of
an animal
_____________________ 11. an organ through which nutrients and wastes are
exchanged between the mother and developing
offspring
Underlying content Copyright by Holt, Rinehart and Winston. Additions and changes to the underlying
content are the responsibility of the instructor.
Holt California Life Science
38
Introduction to Animals
Name ______________________________ Class __________________ Date __________________
Vocabulary and Section Summary B continued
X G H H
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SECTION SUMMARY
Read the following section summary.
• The animal kingdom can be divided into two main groups: invertebrates and
vertebrates. Invertebrates do not have backbones. Vertebrates have backbones.
• Sponges, cnidarians, flatworms, roundworms, mollusks, annelids, arthropods,
and echinoderms are groups of invertebrates.
• Fish, amphibians, reptiles, birds, and mammals are groups of vertebrates.
• Invertebrate bodies can be asymmetrical, radially symmetrical, or bilaterally
symmetrical. Some invertebrates have different body symmetries at different
stages in their life cycle.
• Most vertebrate bodies have bilateral symmetry.
• Many invertebrates reproduce by asexual reproduction and sexual reproduction.
Most vertebrates reproduce only by sexual reproduction.
Underlying content Copyright by Holt, Rinehart and Winston. Additions and changes to the underlying
content are the responsibility of the instructor.
Holt California Life Science
39
Introduction to Animals
Name ______________________________ Class __________________ Date __________________
Skills Worksheet
Vocabulary and Section Summary B
Invertebrates
VOCABULARY
After you finish reading the section, try this puzzle! Use the clues below to
unscramble the letters, and write the word in the space provided.
1. any part of a larger structure, such as the body of an organism, that is set off
by natural or arbitrary boundaries: EEGSTMN
_______________________________________________________________
2. a circulatory system in which the circulatory fluid is not contained entirely
within vessels: LESTMYCICESAYNTROUPOR
_______________________________________________________________
3. a circulatory system in which the heart circulates blood through a network of
vessels that form a closed loop: UCCYTAYROSLRLSMICDOSEET
_______________________________________________________________
4. a process in the life cycle of many animals during which a rapid change from
the immature organism to the adult takes place: SMOPROASHETMI
_______________________________________________________________
5. in insects, a network of tubes inside the body that performs respiration:
ARCHEAT
_______________________________________________________________
6. specialized areas of the nervous system that collect information from outside
and inside the body: ENSSE ONRGAS
_______________________________________________________________
7. a specialized area of the nervous system that acts as the control center of the
functions of the body: NRABI
_______________________________________________________________
8. a process in which some insects shed their exoskeleton several times:
GNOMLTI
_______________________________________________________________
Underlying content Copyright by Holt, Rinehart and Winston. Additions and changes to the underlying
content are the responsibility of the instructor.
Holt California Life Science
40
Introduction to Animals
Name ______________________________ Class __________________ Date __________________
Vocabulary and Section Summary B continued
SECTION SUMMARY
Read the following section summary.
• Invertebrate bodies are asymmetrical, have radial symmetry, or bilateral
symmetry.
• The bodies of many invertebrates are divided into segments.
• Invertebrates have protective outer coverings that provide support and serve as a
place for muscles to attach.
• Invertebrates may have many basic organ systems, such as a respiratory system,
a circulatory system, a digestive system, an excretory system, a nervous system,
and a reproductive system.
• Invertebrates reproduce asexually and sexually. Invertebrates develop from
embryos into larvae and from larvae into adults.
Underlying content Copyright by Holt, Rinehart and Winston. Additions and changes to the underlying
content are the responsibility of the instructor.
Holt California Life Science
41
Introduction to Animals
Name ______________________________ Class __________________ Date __________________
Skills Worksheet
Vocabulary and Section Summary B
Vertebrates
VOCABULARY
After you finish reading the section, try this puzzle! Use the clues below to write
the terms being described in the blanks on the next page. Then, write the boxed
letters in the space provided to spell out a phrase related to animals.
1. a flexible and strong connective tissue
2. nerves that carry impulses from the body to the brain
3. the wider and shorter portion of the intestine that removes water from mostly
digested food and turns the waste into semisolid feces, or stool
4. nerves that carry command impulses throughout the body from the brain
5. the organ between the stomach and the large intestine where most of the
breakdown of food happens and most of the nutrients from food are absorbed
6. vessels that carry blood to the heart
7. the front of the body of a vertebrate
8. the upper body surface or back of a vertebrate
9. vessels that carry blood away from the heart
10. the back of the body of a vertebrate
11. the lower surface or belly of a vertebrate
Underlying content Copyright by Holt, Rinehart and Winston. Additions and changes to the underlying
content are the responsibility of the instructor.
Holt California Life Science
42
Introduction to Animals
Name ______________________________ Class __________________ Date __________________
Vocabulary and Section Summary B continued
1. __
__ __ __ __ __ __
2. __ __ __ __ __ __ __
3. __ __ __ __ __
4.
__ __ __ __
5. __ __
__ __ __ __
__ __ __ __ __ __ __
__ __ __ __ __ __
__
__ __ __ __ __ __ __
6. __ __ __
7.
__ __ __ __ __ __
8.
__ __ __ __
9.
__ __ __ __ __ __
10.
__ __ __ __ __ __ __
11. __ __ __
__ __
12. What is the phrase?
__ __ __ __ __ __ __
__ __ __ __ __
SECTION SUMMARY
Read the following section summary.
• Skin protects the body from the environment. Skin of vertebrates may be
covered in scales, feathers, or fur.
• Most vertebrates have an endoskeleton made of bone. The endoskeleton
provides support, protection, and a place for muscles to attach.
• Major organ systems of vertebrates are the respiratory system, circulatory
system, digestive system, excretory system, nervous system, and reproductive
system.
• Cells of embryos differentiate and specialize as the embryo develops.
• The amount of parental care given to offspring varies among species of
vertebrates.
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43
Introduction to Animals
Name ______________________________ Class __________________ Date __________________
Skills Worksheet
Reinforcement
Who Am I?
Complete this worksheet after you finish reading the section “Invertebrates.”
When you hear the word “animal,” what usually comes to mind? Dogs, cats, farm
animals, maybe birds or reptiles. While these are all animals, they happen to be
vertebrates and are just a small portion of the total animal types on Earth. In fact,
the largest group of animals, by far, is the invertebrates.
See how much you know about invertebrates by filling in each blank below
with one of the following invertebrate animals: grasshopper, sponge, beetle, snail,
hydra, and butterfly. Each animal is described only once.
1. I have many faces—and bodies—throughout my life. I start as an egg, change
into a larva, wrap myself up in a chrysalis, and finally appear in my
adult form. I am a(n) ______________________.
2. I am different from most of the others in this lineup. I have an asymmetrical
body plan. My body support is also unique—a jelly-like material and tiny
glassy structures. I am a(n) ______________________.
3. I carry my body support on my back. Don’t worry, it’s not as heavy as it looks.
I have a more advanced digestive system than many of the others—a
mouth, stomach, intestines, and anus. I am a(n) ______________________.
4. I am an insect. My respiratory system has a network of tubes, called tracheae,
along the sides of my body. These tubes allow me to exchange oxygen and
carbon dioxide in and out of my body. I am a(n)
______________________.
5. I’m really a very simple sort of invertebrate. My nerve cells are rather
scattered; they form a kind of nerve net. I reproduce by budding, and my
offspring look exactly like me. I am a(n) ______________________.
6. I’m a bit like one of my other invertebrate friends listed here. I also undergo
metamorphosis, but I take a bit of a shortcut. From the egg, I go directly to the
nymph stage. At that point, I look just like a little adult and grow until
I’m full size. I am a(n) ______________________.
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Introduction to Animals
Name ______________________________ Class __________________ Date __________________
Skills Worksheet
Critical Thinking
Killer Sponge?!
You probably don’t think of a sponge as being a predator, and in most cases,
you would be right. However, scientists have discovered a sponge that makes its
home in the nutrient-deficient waters of sea caves about 20 m below the surface
and has evolved a unique way of obtaining food.
Unlike most sponges, which are typically filter feeders, these sponges have
developed tentacles with which they can ensnare prey. Once the prey has been
snagged, the sponge wraps tentacles around the unfortunate animal until it can no
longer move, and new tentacles grow over the animal until it is completely
covered. Once the prey is covered, the sponge slowly digests the animal, gaining
energy that would otherwise be unavailable in its low-nutrient environment.
MAKING COMPARISONS
1. How is this sponge different from other sponges?
_______________________________________________________________
_______________________________________________________________
_______________________________________________________________
_______________________________________________________________
DEMONSTRATING REASONED JUDGEMENT
2. Why do you think the cave sponge has developed a different method of
feeding?
_______________________________________________________________
_______________________________________________________________
_______________________________________________________________
_______________________________________________________________
3. The closest relative to the cave sponge lives 8,840 m below the sea surface.
How is the cave environment similar to an environment 8,840 m below the sea
surface?
_______________________________________________________________
_______________________________________________________________
_______________________________________________________________
_______________________________________________________________
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Introduction to Animals
Name ______________________________ Class __________________ Date __________________
Critical Thinking continued
THINKING LOGICALLY
4. Why would this article appear in a magazine called Amazing Adaptations?
_______________________________________________________________
_______________________________________________________________
_______________________________________________________________
_______________________________________________________________
_______________________________________________________________
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Introduction to Animals
Name ______________________________ Class __________________ Date __________________
Activity
SciLinks Activity
ANIMAL TRADING CARDS
Go to www.scilinks.org to find links related
to vertebrates and invertebrates. Type in the
keyword HY71603. Then, use the links to find
information about vertebrate and invertebrate
animals.
1. In the space provided below, draw
pictures of one example each type of vertebrate and type of invertebrate
animals. Next, fill in the information on each animal in the spaces provided.
Finally, cut out the cards, and exchange them with other students. Do not use
an animal mentioned in your book. Be ORIGINAL
Invertebrate
Name:
Body Plan:
Reproduction:
Habitat:
Interesting Fact:
Name:
Body Plan:
Reproduction:
Habitat:
Interesting Fact:
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Introduction to Animals
Name ______________________________ Class __________________ Date __________________
Name:
Body Plan:
Reproduction:
Habitat:
Interesting Fact:
Name:
Body Plan:
Reproduction:
Habitat:
Interesting Fact:
Name:
Body Plan:
Reproduction:
Habitat:
Interesting Fact:
Vertebrate
Name:
Body Plan:
Reproduction:
Habitat:
Interesting Fact:
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48
Introduction to Animals
Name ______________________________ Class __________________ Date __________________
Skills Worksheet
Section Review
What Is an Animal?
USING VOCABULARY
1. Write an original definition for embryo and consumer.
_______________________________________________________________
_______________________________________________________________
UNDERSTANDING CONCEPTS
2. Identifying What is differentiation?
_______________________________________________________________
_______________________________________________________________
3. Describing Starting at the level of the cell, describe the levels of structural
organization in animals.
_______________________________________________________________
_______________________________________________________________
CRITICAL THINKING
4. Making Comparisons What are the two main kinds of reproduction in
animals? How do the kinds of reproduction differ?
_______________________________________________________________
_______________________________________________________________
_______________________________________________________________
5. Identifying Relationships A fish tank contains water, chemicals, fish, snails,
algae, and gravel. Which of these items are alive? Which of these items are
animals? Why are some of the living organisms not classified as animals?
_______________________________________________________________
_______________________________________________________________
_______________________________________________________________
_______________________________________________________________
_______________________________________________________________
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Introduction to Animals
Name ______________________________ Class __________________ Date __________________
Section Review continued
6. Making Inferences Could a parrot fly if it did not have muscle cells? Explain.
_______________________________________________________________
_______________________________________________________________
_______________________________________________________________
INTERPRETING GRAPHICS
The graph shows body temperatures of organism A and organism B and shows
the ground temperature. Use the graph below to answer the next two questions.
7. Evaluating Data How do the body temperatures of the two organisms change
as the ground temperature changes?
_______________________________________________________________
_______________________________________________________________
_______________________________________________________________
_______________________________________________________________
8. Making Inferences Which organism is probably an ectotherm? Which
organism is probably an endotherm? Explain.
_______________________________________________________________
_______________________________________________________________
_______________________________________________________________
_______________________________________________________________
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50
Introduction to Animals
Name ______________________________ Class __________________ Date __________________
Skills Worksheet
Section Review
The Animal Kingdom
USING VOCABULARY
1. Write an original definition for exoskeleton.
_______________________________________________________________
2. Use the following terms in the same sentence: invertebrate and vertebrate, and
placenta.
_______________________________________________________________
_______________________________________________________________
UNDERSTANDING CONCEPTS
3. Describing Describe the kinds of cnidarian body forms and cnidarian stinging
cells.
_______________________________________________________________
_______________________________________________________________
4. Identifying Name two characteristics that are found in mollusks.
_______________________________________________________________
_______________________________________________________________
5. Comparing What are two main differences between a sponge and a
roundworm?
_______________________________________________________________
_______________________________________________________________
6. Identifying Identify one similarity and one difference between vertebrates and
other chordates.
_______________________________________________________________
_______________________________________________________________
7. Classifying Into what group would you classify a female organism that is
covered in fur and that provides milk for its young?
_______________________________________________________________
_______________________________________________________________
_______________________________________________________________
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Introduction to Animals
Name ______________________________ Class __________________ Date __________________
Section Review continued
CRITICAL THINKING
8. Applying Concepts Explain why adult amphibians have to live near water or in a very
wet habitat.
_______________________________________________________________
_______________________________________________________________
INTERPRETING GRAPHICS
Use the two diagrams below to answer the next two questions.
9. Making Comparisons What kind of skeleton does the organism in (a) have? What
kind of skeleton does the organism in (b) have?
____________________________________________________________________
____________________________________________________________________
10. Identifying Relationships Could you classify these two organisms as an invertebrate
or a vertebrate based on only the kind of the skeleton they have? Explain.
____________________________________________________________________
____________________________________________________________________
____________________________________________________________________
____________________________________________________________________
____________________________________________________________________
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Introduction to Animals
Name ______________________________ Class __________________ Date __________________
Section Review continued
MATH SKILLS
11. Making Calculations A bird that weighs 15 g eats 10 times its weight in food
in a week. Calculate how much food the bird eats in a day. Show your work
below.
CHALLENGE
12. Analyzing Relationships What is the relationship between the kind of eggs
reptiles produce and where reptiles can live?
_______________________________________________________________
_______________________________________________________________
_______________________________________________________________
_______________________________________________________________
_______________________________________________________________
_______________________________________________________________
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53
Introduction to Animals
Name ______________________________ Class __________________ Date __________________
Skills Worksheet
Section Review
Invertebrates
UNDERSTANDING CONCEPTS
1. Describing Explain why respiration is important. Be sure to include an
example of an invertebrate respiratory system.
_______________________________________________________________
_______________________________________________________________
_______________________________________________________________
2. Comparing How is the support in the body of a sponge different from the
support in the body of an insect?
_______________________________________________________________
_______________________________________________________________
_______________________________________________________________
3. Identifying How do insects remove wastes that are produced by cells in their
bodies?
_______________________________________________________________
_______________________________________________________________
_______________________________________________________________
4. Comparing In the life cycle of a grasshopper, what are two main differences
between nymphs and adults?
_______________________________________________________________
_______________________________________________________________
5. Inferring If an animal has a head, which kind of body symmetry would you
expect the animal to have?
_______________________________________________________________
_______________________________________________________________
_______________________________________________________________
_______________________________________________________________
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Introduction to Animals
Name ______________________________ Class __________________ Date __________________
Section Review continued
CRITICAL THINKING
6. Analyzing Processes Describe metamorphosis in the life cycle of a butterfly
and in the life cycle of a grasshopper.
_______________________________________________________________
_______________________________________________________________
_______________________________________________________________
7. Making Comparisons Compare an open circulatory system and a closed
circulatory system.
_______________________________________________________________
_______________________________________________________________
_______________________________________________________________
_______________________________________________________________
8. Expressing Opinions Why are earthworms in a different group than
roundworms? Explain.
_______________________________________________________________
_______________________________________________________________
_______________________________________________________________
9. Applying Concepts Why can’t insects see in complete darkness?
_______________________________________________________________
_______________________________________________________________
_______________________________________________________________
MATH SKILLS
10. Making Calculations A sea urchin lost 12 of its 178 spines in a storm. What
percentage of its spines does the sea urchin still have? Show your work below.
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Introduction to Animals
Name ______________________________ Class __________________ Date __________________
Section Review continued
CHALLENGE
11. Applying Concepts If the head of an insect became stuck underwater, would
the insect drown? Explain your answer.
_______________________________________________________________
_______________________________________________________________
_______________________________________________________________
_______________________________________________________________
_______________________________________________________________
12. Making Inferences What other body part do invertebrates that have ears or
noses have?
_______________________________________________________________
_______________________________________________________________
_______________________________________________________________
_______________________________________________________________
_______________________________________________________________
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Introduction to Animals
Name ______________________________ Class __________________ Date __________________
Skills Worksheet
Section Review
Vertebrates
UNDERSTANDING CONCEPTS
1. Demonstrating How do different kinds of cells develop in an embryo?
_______________________________________________________________
_______________________________________________________________
2. Describing Describe the structure of the backbone and what it provides the
vertebrate body.
_______________________________________________________________
_______________________________________________________________
3. Identifying What kind of circulatory system do vertebrates have?
_______________________________________________________________
_______________________________________________________________
INTERPRETING GRAPHICS
Use the graph below to answer the next two questions.
4. Evaluating How many fish species in the United States are endangered?
_______________________________________________________________
_______________________________________________________________
5. Calculating What is the total number of endangered and threatened fish
species in the United States? Show your work below.
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Introduction to Animals
Name ______________________________ Class __________________ Date __________________
Section Review continued
CRITICAL THINKING
6. Making Comparisons How does gas exchange in gills differ from gas
exchange in lungs?
_______________________________________________________________
_______________________________________________________________
7. Applying Concepts What is an advantage and a disadvantage of depositing a
large number of eggs?
_______________________________________________________________
_______________________________________________________________
8. Applying Concepts How does an egg become fertilized? Is this sexual or
asexual reproduction? Explain your answer.
_______________________________________________________________
_______________________________________________________________
_______________________________________________________________
CHALLENGE
9. Making Inferences What factors might limit the maximum body size to which
land vertebrates can grow?
_______________________________________________________________
_______________________________________________________________
_______________________________________________________________
_______________________________________________________________
_______________________________________________________________
10. Applying Concepts Why might large ears be better able to hear a sound than
small ears?
_______________________________________________________________
_______________________________________________________________
_______________________________________________________________
_______________________________________________________________
_______________________________________________________________
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Introduction to Animals
Name ______________________________ Class __________________ Date __________________
Skills Worksheet
Chapter Review
USING VOCABULARY
1. Academic Vocabulary Which word best completes the following sentence:
“Through ______________________ the cells in a developing embryo
specialize to develop into different kinds of cells.”
For each pair of terms, explain how the meanings of the terms differ.
2. endoskeleton and exoskeleton
_______________________________________________________________
_______________________________________________________________
3. invertebrate and vertebrate
_______________________________________________________________
_______________________________________________________________
4. asexual reproduction and sexual reproduction
_______________________________________________________________
_______________________________________________________________
UNDERSTANDING CONCEPTS
Multiple Choice
_____ 5. The sea urchin’s body is organized around the organism’s center, like
the spokes on a wheel. What kind of symmetry does the sea urchin
have?
a. bilateral
b. radial
c. asymmetrical
d. unilateral
_____ 6. Members of which of the following groups of invertebrates have
segmented bodies?
a. mollusks
b. sea anemones
c. roundworms
d. arthropods
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Introduction to Animals
Name ______________________________ Class __________________ Date __________________
Chapter Review continued
_____ 7. What would happen if the gills of a fish stopped working?
a. The fish would probably die.
b. The fish would make its own oxygen.
c. The fish would make more carbon dioxide.
d. The fish would not be able to maintain its body temperature.
_____ 8. Which of the following is NOT a function of the endoskeleton?
a. The endoskeleton provides a place for muscles to attach.
b. The endoskeleton supports the body from the outside of the body.
c. The endoskeleton supports the body from the inside of the body.
d. The endoskeleton protects the organs of the body.
Short Answer
9. Listing List the seven basic characteristics of animals.
_______________________________________________________________
_______________________________________________________________
_______________________________________________________________
10. Inferring Some insects develop from nymphs into adults. What kind of
metamorphosis do these insects undergo? Explain.
_______________________________________________________________
_______________________________________________________________
_______________________________________________________________
11. Comparing How does fragmentation in sponges differ from reproduction in
reptiles?
_______________________________________________________________
_______________________________________________________________
_______________________________________________________________
12. Listing What are the levels of structural organization in the body of a shark?
_______________________________________________________________
_______________________________________________________________
_______________________________________________________________
_______________________________________________________________
_______________________________________________________________
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Introduction to Animals
Name ______________________________ Class __________________ Date __________________
Chapter Review continued
INTERPRETING GRAPHICS
The picture below shows a member of the animal kingdom. Use the picture to
answer the next three questions.
13. Identifying Name the body segments labeled a, b, and c.
_______________________________________________________________
_______________________________________________________________
14. Identifying To which segment are the legs of this animal attached?
_______________________________________________________________
15. Analyzing Into which group would you classify this animal? Explain.
_______________________________________________________________
_______________________________________________________________
_______________________________________________________________
_______________________________________________________________
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Introduction to Animals
Name ______________________________ Class __________________ Date __________________
Chapter Review continued
WRITING SKILLS
16. Explaining Ideas What is the relationship between bones and muscles?
Describe how these two kinds of structures help vertebrates move around.
_______________________________________________________________
_______________________________________________________________
_______________________________________________________________
_______________________________________________________________
_______________________________________________________________
_______________________________________________________________
_______________________________________________________________
_______________________________________________________________
_______________________________________________________________
_______________________________________________________________
_______________________________________________________________
_______________________________________________________________
_______________________________________________________________
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Introduction to Animals
Name ______________________________ Class __________________ Date __________________
Chapter Review continued
CRITICAL THINKING
17. Concept Mapping Use the following terms to create a concept map:
vertebrates, bilateral symmetry, fish, sponge, radial symmetry, sea urchin,
sexual reproduction, asymmetrical, asexual reproduction, and invertebrates.
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Introduction to Animals
Name ______________________________ Class __________________ Date __________________
Chapter Review continued
18. Identifying Relationships Why are vertebrates classified as chordates?
_______________________________________________________________
_______________________________________________________________
19. Making Comparisons Describe three groups of mammals and how they differ.
_______________________________________________________________
_______________________________________________________________
_______________________________________________________________
20. Predicting Consequences If differentiation in an embryo is stopped, predict
what is likely to happen to the embryo. Explain.
_______________________________________________________________
_______________________________________________________________
_______________________________________________________________
21. Analyzing Methods Could you identify the entire life cycle of an animal by
studying only the adult forms of that animal? Explain.
_______________________________________________________________
_______________________________________________________________
_______________________________________________________________
22. Analyzing Relationships How do the eyes of a dog help the dog fetch a ball?
_______________________________________________________________
_______________________________________________________________
_______________________________________________________________
23. Predicting Consequences Cats are endotherms, and geckos are ectotherms.
Describe what would happen to a cat and a gecko if they were caught in a
snowstorm.
_______________________________________________________________
_______________________________________________________________
_______________________________________________________________
_______________________________________________________________
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Introduction to Animals
Name ______________________________ Class __________________ Date __________________
Chapter Review continued
24. Making Inferences A bird may have only two or three offspring at a time. A
sea turtle may lay 100 eggs at a time. Which of these two organisms is more
likely to provide its offspring with more parental care?
_______________________________________________________________
_______________________________________________________________
_______________________________________________________________
25. Making Comparisons Compare the circulatory system in an insect with a fish.
_______________________________________________________________
_______________________________________________________________
_______________________________________________________________
INTERPRETING GRAPHICS
The graph below shows the kinds of amphibians that are threatened or
endangered in the United States. Use the graph to answer the next two questions.
26. Making Conversions If the total number of threatened and endangered
amphibian species in the United States is 22, how many more species of
salamanders are threatened or endangered than species of frogs and toads?
Show your work below.
27. Making Inferences What do you expect to happen to the percentage of toads in
the pie graph as endangered toad species become extinct?
_______________________________________________________________
_______________________________________________________________
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Introduction to Animals
Name ______________________________ Class __________________ Date __________________
Chapter Review continued
MATH SKILLS
28. Making Calculations All of the females in a boar population produce exactly
10 offspring during their lifetime. What percentage of each female’s offspring
must survive so that the number of individuals in the population remains
constant? Show your work below.
CHALLENGE
29. Making Inferences On land, only animals that have endoskeletons become
very large. Why are vertebrates on land larger than invertebrates on land?
_______________________________________________________________
_______________________________________________________________
_______________________________________________________________
_______________________________________________________________
_______________________________________________________________
_______________________________________________________________
_______________________________________________________________
_______________________________________________________________
_______________________________________________________________
_______________________________________________________________
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Introduction to Animals
TEACHER RESOURCES
Assessment
Chapter Pretest
Teacher Notes and Answer Key
The Pretest questions are designed to help you determine the prior knowledge of
your students. Some questions test whether students have mastered the
background knowledge they need to understand the content you are about to
teach. Other questions test your students’ prior knowledge of the content you are
about to teach. Use the Pretest with the Test Doctors and diagnostic teaching tips
in these notes pages to help you tailor your instruction to your students’ specific
needs.
TEST DOCTOR
The following Pretest questions have been diagnosed by the Test Doctor. Find out
what might be causing your students’ “ailing” answers. Each Test Doctor is
followed by a diagnostic teaching tip to help you address students’ learning needs.
QUESTION NUMBER
CORRECT ANSWER
STANDARD
1
2
3
4
5
6
7
8
9
B
D
A
C
A
C
D
D
B
7.1.d
7.5.a
7.5.f
7.1.b
7.2.a
7.5.a
7.5.b
7.5.c
7.1.f
Question 1 asks students to identify the part of the plant where most of
photosynthesis occurs.
A Incorrect. The flower of a plant has structures for sexual reproduction and not
for photosynthesis.
B Correct. Most photosynthesis occurs in the leaves. They have many structures
for absorbing sunlight and carbon dioxide.
C Incorrect. The roots are most often below ground and absorb water and
nutrients from the soil. They are not specialized for absorbing sunlight.
D Incorrect. The stems support the plant and transport water and nutrients to the
leaves for photosynthesis. Cells in the stems of some plants do conduct
photosynthesis but most of the photosynthesis occurs in the leaves of plants.
Diagnostic Teaching Tip: Students who have difficulty with this question
should receive further visual instruction on the structures of a plant and their
functions. Emphasize the size, surface area of leaves, the growth habit of the
plant, and the amount of available sunlight in the geographic region.
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Introduction to Animals
TEACHER RESOURCES
Chapter Pretest continued
Question 2 asks students to identify the physical process that occurs in humans
that is similar to transpiration in plants.
A Incorrect. Metabolism is the sum of many processes that occur in both plants
and humans when food is broken down and energy is released. Metabolism also
releases heat and does not cool the body.
B Incorrect. Respiration (in the cell and the exchange of gases in the body) occurs
in both plants and humans but is not the primary process by which the body is
cooled.
C Incorrect. Shivering is a reaction that occurs in the human body when it is cold.
The movement helps to warm the body by releasing heat energy.
D Correct. Sweating is the process that occurs in humans when water is released
through skin cells to cool the body as it evaporates from the skin.
Diagnostic Teaching Tip: Students who answer this question incorrectly
should study how the release of water from plants and animals has a cooling
effect as the water vapor evaporates. Diagrams of human skin cells and other
visuals should show how the process of sweating releases water through
these cells similar to how it is released through stomata in plants.
Question 3 asks students to identify the part of a flower that produces sperm, the
male sex cells.
A Correct. Anthers are the structures that produce pollen, which is the male
sperm.
B Incorrect. The filament is the part of the stamen that supports the anther and
positions it for pollen transfer.
C Incorrect. The stigma is a sticky part of the flower that traps the pollen grains.
D Incorrect. The style is the part of the flower that connects the stigma to the
ovary.
Diagnostic Teaching Tip: Students who have difficulty with this question
might benefit from diagrams of the structures in a flower, the function of
each structure, and how fertilization works. Give examples of many shapes
of flowers. Focus on the way insects are attracted to the flower, touch the
pollen, and carry the pollen to be deposited on another flower.
Question 4 asks students to know why leaves change color in the fall.
A Incorrect. Lack of water is not the stimulus for the breakdown of chlorophyll.
B Incorrect. Colder temperatures occur during the autumn, but temperature
change does not break down the chlorophyll pigment in leaves.
C Correct. Green chlorophyll begins to break down in autumn due to the
shortening of daylight hours. This allows other pigments in the leaves to show.
D Incorrect. Lack of carbon dioxide can have an impact on photosynthesis, but
this does not cause chlorophyll to break down in the fall.
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Introduction to Animals
TEACHER RESOURCES
Chapter Pretest continued
Diagnostic Teaching Tip: Students who have trouble answering this question
should review the connection between the amount of sunlight and
photosynthesis. Include illustrations of all the natural pigments in leaves,
and discuss how the stimulus from the environment (change in the hours of
daylight) results in the breakdown of the green chlorphyll pigment.
Question 5 asks students to identify a product of sexual reproduction in a plant.
A Correct. A fruit contains the seeds, which are the result of fertilization in
sexual reproduction.
B Incorrect. Plantlets are pieces of the mother plant that fall off and start new
genetically identical plants.
C Incorrect. Runners are roots or stems that spread out from the mother plant and
produce new plants.
D Incorrect. Tubers are underground stems or roots of a mother plant that sprout
new plants that are genetically identical to the mother plant.
Diagnostic Teaching Tip: Students who have difficulty answering this
question correctly should study the process of pollination and the
contribution of both sperm (pollen) and eggs in fertilization. Explain that the
developing embryo from sexual reproduction is the seed and that the ovule
becomes a fruit to protect the seed. Contrast this instruction with examples
of identical offspring developing from mother plants by runner, offsets, and
tubers in asexual reproduction.
Question 6 asks students to demonstrate an understanding of the organization of
cells to form tissues, organs, and organ systems.
A Incorrect. Although cells are the smallest level, tissues come before organs in
the hierarchy.
B Incorrect. Although cells are smallest level, the last three levels are reversed.
C Correct. The hierarchy of organization moves from smallest and least complex
to largest and most complex.
D Incorrect. Organ system is the highest level and should be placed at the end of
the list.
Diagnostic Teaching Tip: Students who have difficulty with this question
should examine visuals and models that show how cells that look similar and
work together combine in tissues. Visuals should show how organs are made
up of many types of tissues working together and how organ systems are
made up of many organs all working together to perform a necessary
function. Be sure to emphasize Section 1, “What Is an Animal?,” in Chapter
14, “Introduction to Animals.” Students must know that animals have levels
of organization for structure and function in order to master standard 7.5.a.
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Introduction to Animals
TEACHER RESOURCES
Chapter Pretest continued
Question 7 asks students to identify the digestive system of a snail.
A Incorrect. The nervous system includes sense organs and a brain.
B Incorrect. The circulatory system transports many substances in blood.
C Incorrect. The respiratory system includes gills or lungs.
D Correct. The digestive system includes the mouth, stomach, intestine, and anus.
Diagnostic Teaching Tip: Students who have difficulty answering this
question correctly might benefit from a visual introduction to the basic organ
systems of invertebrates. Be sure to emphasize Section 3, “Invertebrates,” in
Chapter 14, “Introduction to Animals.” Students must know that organ
systems function because of the contributions of individual organs, tissues,
and cells in order to master standard 7.5.b.
Question 8 asks students to identify common animals as either vertebrates or
invertebrates.
A Incorrect. Sponges are invertebratess that do not have endoskeletons. Sponges
are supported by a jelly-like material and small, glassy structures.
B Incorrect. Insects are invertebrates with exoskeletons.
C Incorrect. Sea stars are invertebrate echinoderms. Students may think they have
a skeleton because of the shape of their legs and their movement.
D Correct. Snakes are vertebates and have an internal skeleton and backbone.
Students may not think snakes have an internal skeleton because of the way
they move and their similarity to worms.
Diagnostic Teaching Tip: If students have difficulty with this question,
emphasize the five groups of animals that have an internal skeleton: birds,
fish, amphibians, reptiles, and mammals. Provide many visual examples of
what the internal bone structures of these animals look like. Because of the
snake’s characteristics, many students will be surprised to learn that snakes
have an internal skeleton. Be sure to emphasize Section 1, “What Is an
Animal?,” in Chapter 14, “Introduction to Animals.” Students must know
how bones and muscles work together to provide a structural framework for
movement in order to master standard 7.5.c.
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Introduction to Animals
TEACHER RESOURCES
Chapter Pretest continued
Question 9 asks students to identify the process by which cells that perform
different functions develop different structures.
A Incorrect. Fragmentation is a kind of asexual reproduction in which parts of an
organism break off and then develop into new individuals.
B Correct. Differentiation is the process by which cells that perform different
functions develop different structures.
C Incorrect. Segmentation describes any part of a larger structure, such as the
body of an organism, that is set off by natural or arbitrary boundaries.
D Incorrect. Budding is a kind of asexual reproduction in which part of the
parent organism develops into a new organism.
Diagnostic Teaching Tip: For students who have difficulty answering this
question correctly, have the class brainstorm different cells of the body that
are differentiated to perfom specialized functions. An example is some nerve
cells that grow very long so that they are able to carry elecrical signals from
your spine to your feet. Be sure to emphasize Section 1, “What Is an
Animal?,” in Chapter 14, “Introduction to Animals.” Students must know
that as multicellular organisms develop, their cells differentiate in order to
master standard 7.1.f.
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Introduction to Animals
Name ______________________________ Class __________________ Date __________________
Assessment
Chapter Pretest
_____ 1. Clara is studying plants. She wants to describe the functions the
different parts of a plant perform for her science report. Where should
Clara say that most of the process of photosynthesis occurs?
A flowers
B leaves
C roots
D stems
_____ 2. Plants have a special reaction that allows them to keep from being
overheated. The leaves let water evaporate and escape through stomata
through a process called transpiration. There is a similar process that
occurs in the human body to prevent the body from becoming
overheated. What is this process called?
A metabolism
B respiration
C shivering
D sweating
_____ 3. Flowers have both male and female parts that function in reproduction.
Which part of the flower produces the male sex cells?
A anther
B filament
C stigma
D style
_____ 4. Shane noticed that during autumn the leaves on the trees begin to turn
from green to yellow, orange, and red. He wonders what causes the
leaves to change color. He did some research and recalled that water,
sunlight, and carbon dioxide are necessary for plants to form leaves.
What is the main reason that leaves start changing color during
autumn?
A lack of water
B colder temperatures
C fewer daylight hours
D lack of carbon dioxide
_____ 5. Plants reproduce in many different ways. Which of the following is a
product of sexual reproduction?
A fruit
B plantlet
C runner
D tuber
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Introduction to Animals
Name ______________________________ Class __________________ Date __________________
Chapter Pretest continued
_____ 6. Latesha is trying to remember the way cells are organized in our bodies
so that they can perform all the life functions. Which of the following
shows the order from the most simple unit to the most complex unit?
A cell, organ, tissue, organ system
B cell, organ system, organ, tissue
C cell, tissue, organ, organ system
D cell, organ system, tissue, organ
_____ 7. Which of the following organ systems is represented in the illustration
of the snail below?
A
B
C
D
nervous system
circulatory system
respiratory system
digestive system
_____ 8. Dana is studying the characteristics of different types of animals.
Which of the following animals might she be surprised to learn has a
body with a hard, internal skeleton?
A sponge
B insect
C sea star
D snake
_____ 9. The cells of multicellular organisms become specialized through a
process in which cells that perform different functions develop
different structures. This process is called
A fragmentation.
B differentiation.
C segmentation.
D budding.
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Introduction to Animals
Name ______________________________ Class __________________ Date __________________
Assessment
Section Quiz
Section: What Is an Animal?
Match the correct description with the correct term. Write the letter in the space
provided.
a. sexual reproduction
b. differentiation
c. asexual
_____ 1. an organism that eats other
organisms or organic matter
_____ 2. a body cavity that protects internal
organs
reproduction
d. coelom
e. consumer
_____ 3. reproduction in which sex cells
from two parents unite to produce
offspring
_____ 4. reproduction in which one parent produces genetically identical offspring
_____ 5. the process in which the structure and function of the parts of an organism
change to enable specialization of those parts
Write the letter of the correct answer in the space provided.
_____ 6. Which of the following is a group of the same type of cells?
a. tissues
c. muscles
b. organs
d. kidneys
_____ 7. All animals
a. are multicellular.
b. have cell walls.
c. are single celled.
d. reproduce asexually.
_____ 8. What type of body plan is found in most animals?
a. coelom
b. bilateral symmetry
c. asymmetrical
d. radial symmetry
_____ 9. What is the type of asexual reproduction in which part of an organism
develops into an identical new organism?
a. budding
c. fertilization
b. differentiation
d. fragmentation
_____ 10. What kinds of cells are responsible for movement in animals?
a. red blood cells
b. white blood cells
c. photosynthetic cells
d. muscle cells
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Introduction to Animals
Name ______________________________ Class __________________ Date __________________
Assessment
Section Quiz
Section: The Animal Kingdom
Match the correct description with the correct term. Write the letter in the space
provided.
_____ 1. a hard, external, supporting structure
______ 2. an animal that does not have a
backbone
a.
b.
c.
d.
vertebrate
invertebrate
exoskeleton
endoskeleton
______ 3. an internal skeleton made of bone
and cartilage
______ 4. an animal that has a backbone
Write the letter of the correct answer in the space provided.
_____ 5. How many species of animals do some scientists estimate live on
Earth?
a.
b.
c.
d.
3 million
4 million
5 million
6 million
_____ 6. How do scientists organize animals into groups?
a.
b.
c.
d.
based on the year the animal is discovered
based on DNA only
based on personal preference
based on characteristics, evolutionary relationships, and DNA
_____ 7. What are the two radially symmetrical body plans of cnidarians?
a.
b.
c.
d.
medusa; polyp
larvae; cnidocyte
endoskeleton; exoskeleton
budding; fragmentation
_____ 8. How does a lancelet differ from a vertebrate?
a.
b.
c.
d.
It has a notochord, but no backbone.
It has a backbone, but no notochord.
It has a spine, but no brain.
It has a brain, but no central nervous system.
_____ 9. Which of the following is an example of a cartilaginous fish?
a.
b.
c.
d.
salmon
jellyfish
shark
Garibaldi
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Introduction to Animals
Name ______________________________ Class __________________ Date __________________
Assessment
Section Quiz
Section: Invertebrates
Match the correct description with the correct term. Write the letter in the space
provided.
_____ 1. a part of an organism that is set
off by natural and arbitrary
boundaries
_____ 2. a rapid change from the
immature to the adult form of an
organism
a. open circulatory
b.
c.
d.
e.
system
segment
closed circulatory
system
respiratory system
metamorphosis
_____ 3. a system in which blood
circulates through a closed loop
_____ 4. a system in which blood moves through open spaces
_____ 5. a system that takes in oxygen and releases carbon dioxide
Write the letter of the correct answer in the space provided.
_____ 6. Which of the following structures does NOT provide support for
invertebrate bodies?
a. backbone
c. skin
b. tiny glassy structures
d. exoskeleton
_____ 7. Which of the following body systems eliminates excess water and
waste from cells?
a. respiratory system
b. circulatory system
c. nervous system
d. excretory system
_____ 8. Eyes are examples of what body part?
a. nervous system
c. brain
b. sense organ
d. control center
_____ 9. Which of the following pairs of organisms reproduce only asexually?
a. butterfly; caterpillar
c. hydra; planaria
b. flatworm; earthworm
d. grasshopper; beetle
_____ 10. Which of the following organisms undergoes incomplete
metamorphosis?
a. cockroach
c. butterfly
b. sponge
d. flatworm
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Introduction to Animals
Name ______________________________ Class __________________ Date __________________
Assessment
Section Quiz
Section: Vertebrates
Match the correct description with the correct term. Write the letter in the space
provided.
_____ 1. a flexible and strong connective issue
______ 2. the organ in which most breakdown
of food occurs
a.
b.
c.
d.
small intestine
large intestine
cartilage
lung or gill
______ 3. the organ that turns waste into feces
______ 4. the main respiratory organ in vertebrates
Write the letter of the correct answer in the space provided.
_____ 5. The skull, backbone, and limb bones are all part of a vertebrate’s
a. shell.
b. exoskeleton.
c. endoskeleton.
d. mantle.
_____ 6. What vertebrates are covered in both scales and mucous?
a. reptiles
c. fish
b. amphibians
d. birds
_____ 7. What system is made up of the heart, veins, arteries, and capillaries?
a. respiratory system
b. circulatory system
c. nervous system
d. excretory system
_____ 8. What organ serves as the main control center for the body?
a. sensory nerves
c. spinal cord
b. brain
d. motor nerves
_____ 9. In which of the following ways do most vertebrates reproduce?
a. budding
b. fragmentation
c. asexually
d. sexually
_____ 10. Which part of the endoskeleton is most responsible for helping a
vertebrate to move?
a. skull
c. limb bones
b. backbone
d. cartilage
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Introduction to Animals
Name ______________________________ Class __________________ Date __________________
Assessment
Chapter Test A
Introduction to Animals
MULTIPLE CHOICE
Write the letter of the correct answer in the space provided.
_____ 1. Radial symmetry, bilateral symmetry, and asymmetrical are which of
the following?
a. body plans
b. organ structures
c. animal species
d. body sizes
_____ 2. Which of the following is a group of organs that work together?
a. organism
b. organ system
c. tissue
d. muscle
_____ 3. What is likely to happen to an animal if one of its organ systems fails?
a. The animal will get stronger.
b. The animal will grow replacement organs.
c. The animal will reproduce itself.
d. The animal will die.
_____ 4. Which of the following does NOT make movement in animals
possible?
a. the contraction and relaxation of the brain
b. the contraction and relaxation of muscle cells
c. the connection of muscles to bones
d. the connection of muscles to outer coverings
_____ 5. Besides maintaining body temperature, some birds’ feathers help them
to do which of the following?
a. hear
b. see
c. fly
d. sleep
_____ 6. Which of the following are only found in vertebrates?
a. hearts
b. nerves
c. backbones
d. tentacles
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Introduction to Animals
Name ______________________________ Class __________________ Date __________________
Chapter Test A continued
_____ 7. Which of these is NOT a type of mammal?
a. reptile
b. monotreme
c. placental
d. marsupial
_____ 8. Which of these is NOT a part of a vertebrate’s endoskeleton?
a. skull
b. backbone
c. blood
d. limb bones
_____ 9. Which system includes the small and large intestines?
a. respiratory system
b. excretory system
c. reproductive system
d. circulatory system
_____ 10. To react to sound, the brain sends commands through which of the
following?
a. capillaries
b. veins
c. sensory nerves
d. motor nerves
_____ 11. An animal that lacks a backbone is which of the following?
a. vertebrate
b. invertebrate
c. marsupial
d. monotreme
_____ 12. Which of the following is a hard covering that protects an arthropod?
a. exoskeleton
b. endoskeleton
c. mantle
d. segment
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Introduction to Animals
Name ______________________________ Class __________________ Date __________________
Chapter Test A continued
MATCHING
Match the correct description with the correct term. Write the letter in the space
provided.
_____ 13. the specialization of cells as an
animal develops
_____ 14. a rapid change from the young
to the adult form of an animal
a.
b.
c.
d.
sexual reproduction
budding
metamorphosis
differentiation
_____ 15. a type of reproduction used by
most vertebrates
_____ 16. a type of reproduction used by hydras
Match the correct description with the correct term. Write the letter in the space
provided.
_____ 17. system in which blood flows
through tubes in a closed loop
_____ 18. system in which energy is
derived from food
_____ 19. system in which fluid flows
through open spaces
a. digestive system
b. open circulatory
system
c. respiratory system
d. closed circulatory
system
_____ 20. system in which oxygen enters a vertebrate’s body through lungs or
gills
Match the correct description with the correct term. Write the letter in the space
provided.
_____ 21. body plan of sponges, jellyfish,
and adult corals
_____ 22. body plan of lancelets
a. bilateral symmetry
b. asymmetrical
c. radial symmetry
_____ 23. body plan of a sea star
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Introduction to Animals
Name ______________________________ Class __________________ Date __________________
Chapter Test A continued
FILL IN THE BLANK
Use the terms from the following list to complete the sentences below.
consumer
tracheae
coelom
cartilage
segments
complete metamorphosis
24. During the process of ______________________, a butterfly goes through egg,
larva, pupa, and adult stages.
25. As vertebrates grow, ______________________ is often replaced by harder
bone.
26. The head, thorax, and abdomen of the bee are examples of
______________________.
27. In insects, respiration is performed in a network of tubes called
______________________.
28. A body cavity that protects internal organs is called the
______________________.
29. An organism that eats other organisms is called a(n)
______________________.
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Introduction to Animals
Name ______________________________ Class __________________ Date __________________
Assessment
Chapter Test B
Introduction to Animals
MULTIPLE CHOICE
Write the letter of the correct answer in the space provided.
_____ 1. All animals
a. are single-celled organisms.
b. are multicellular organisms.
c. have cell walls.
d. have backbones.
_____ 2. All animals are either
a. single celled or multicellular.
b. radially symmetrical or bilaterally symmetrical.
c. have backbones or notochords.
d. vertebrates or invertebrates.
_____ 3. In vertebrates, the lungs or gills oxygenate blood, while the
a. heart pumps blood.
b. arteries pump blood.
c. veins pump blood.
d. nerves pump blood.
_____ 4. The skull, backbone, and limb bones make up a vertebrate’s
a. endoskeleton.
b. exoskeleton.
c. mantle.
d. segments.
_____ 5. A group of organs that perform a specific function important to the
survival of an animal is called a(n)
a. cell.
b. tissue.
c. organ system.
d. organism.
_____ 6. Of the more than 1 million species of animals scientists have named,
a. arthropods are the largest group.
b. chordates are the largest group.
c. arthropods are the smallest group.
d. chordates are the smallest group.
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Introduction to Animals
Name ______________________________ Class __________________ Date __________________
Chapter Test B continued
_____ 7. A sponge’s body is supported by
a. an exoskeleton.
b. an endoskeleton.
c. a thick skin.
d. a jelly-like material and tiny, glassy structures.
_____ 8. Which of the following statements is NOT true of sexual reproduction?
a. Most vertebrates reproduce sexually.
b. Offspring of sexual reproduction are genetic duplicates of the parent.
c. A fertilized egg cell divides many times to form an embryo.
d. An embryo’s cells differentiate to perform specialized functions.
_____ 9. Which of the following is true of cnidarians?
a. They are invertebrates with backbones.
b. They have radially symmetrical medusa or polyp body plans.
c. They have a head, thorax, and abdomen.
d. They have an endoskeleton.
_____ 10. A lobster is able to move because groups of contracting and relaxing
muscle cells are attached to its
a. limb bones.
b. backbone.
c. exoskeleton.
d. endoskeleton.
_____ 11. Which of the following is NOT true of a lancelet?
a. They have a notochord.
b. They are marine animals.
c. They are chordates.
d. They develop a backbone and are vertebrates.
_____ 12. When sound reaches the ear, it triggers an impulse through what part of
the nervous system to the brain?
a. motor nerves
b. sensory nerves
c. small intestine
d. large intestine
_____ 13. Because they feed on other organisms to get energy, all animals are
a. consumers.
b. invertebrates.
c. vertebrates.
d. predators.
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Introduction to Animals
Name ______________________________ Class __________________ Date __________________
Chapter Test B continued
_____ 14. Besides helping some birds fly, feathers
a. are also found on some reptiles.
b. are also found on some amphibians.
c. help to maintain body temperature.
d. help to keep the skin moist.
MATCHING
Match the correct description with the correct term. Write the letter in the space
provided.
a. open circulatory
_____ 15. a digestive organ that absorbs
system
nutrients
b. closed circulatory
system
c. small intestine
d. large intestine
e. coelom
ab. tracheae
_____ 16. a body cavity that contains
internal organs
_____ 17. a system in which blood is
circulated through a closed
network of vessels
_____ 18. a digestive organ that creates feces
_____ 19. a network of tubes that performs respiration in insects
_____ 20. a system in which blood moves through open spaces
Match the correct definition with the correct term. Write the letter in the space
provided.
_____ 21. a hard, external, supporting
structure
_____ 22. a flexible and strong connective
tissue
a.
b.
c.
d.
cartilage
segment
endoskeleton
exoskeleton
_____ 23. an internal skeleton made of
bone and cartilage
_____ 24. a part of a larger structure that is set of by boundaries
Match the correct description with the correct term. Write the letter in the space
provided.
_____ 25. how a hydra reproduces
_____ 26. how most vertebrates reproduce
a. sexual reproduction
b. budding
c. fragmentation
_____ 27. how a sponge reproduces asexually
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Introduction to Animals
Name ______________________________ Class __________________ Date __________________
Chapter Test B continued
Match the labels to the drawings. Write the letters in the spaces provided.
_____ 28. egg
_____ 29. larva
_____ 30. pupa
_____ 31. adult
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Introduction to Animals
Name ______________________________ Class __________________ Date __________________
Assessment
Chapter Test C
Introduction to Animals
USING KEY TERMS
Use the terms from the following list to complete the sentences below. Each term
may be used only once. Some terms may not be used.
consumer
sensory nerves
differentiation
motor nerves
digestive system
coelom
segments
closed circulatory system
open circulatory system
1. The specialization of cells in an embryo as it develops is called
______________________.
2. An earthworm’s body is divided into ______________________, each of which
has a set of muscles that can push it through soil
3. An organism that gets its energy from feeding on other organisms is called
a(n) ______________________.
4. Blood gains oxygen in a frog’s respiratory system and is pumped throughout
its body through a closed loop of tubes called a(n) ______________________.
5. When sound reaches the ear, it triggers an impulse that is sent to the brain
through ______________________.
6. The small intestine absorbs nutrients and the large intestine forms feces as
part of the ______________________.
7. Many animals have a body cavity, called a(n) ______________________, that
surrounds and protects groups of organs.
UNDERSTANDING KEY IDEAS
Write the letter of the correct answer in the space provided.
_____ 8. Which of the following is NOT true about animals?
a. They are multicellular.
b. They are consumers.
c. They maintain their body temperatures.
d. They have cell walls.
_____ 9. A vertebrate’s endoskeleton is made up of a
a. skull, notochord, and backbone.
b. notochord, backbone, and limb bones.
c. skull, backbone, and limb bones.
d. skull and backbone.
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Introduction to Animals
Name ______________________________ Class __________________ Date __________________
Chapter Test C continued
_____ 10. The skeletons of all embryos are made up of a flexible and strong
connective tissue called
a. bone.
b. cartilage.
c. vertebrae.
d. segments.
_____ 11. Some scientists estimate there may be more than
a. 3 million species of animals.
b. 10 million species of animals.
c. 13 million species of animals.
d. 20 million species of animals.
_____ 12. Which of the following is NOT true of a jellyfish?
a. It has a medusa rather than polyp form.
b. It is radially symmetrical.
c. It has a head and tail.
d. It is a cnidarian.
_____ 13. How do vertebrates typically reproduce?
a. sexually
b. asexually
c. through fragmentation
d. through budding
14. What are the two main groups of animals, and how are they different?
_______________________________________________________________
_______________________________________________________________
_______________________________________________________________
15. What is an open circulatory system? What type of animal has an open
circulatory system?
_______________________________________________________________
_______________________________________________________________
16. How does the respiratory system of a fish differ from that of mammals?
_______________________________________________________________
_______________________________________________________________
_______________________________________________________________
_______________________________________________________________
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Introduction to Animals
Name ______________________________ Class __________________ Date __________________
Chapter Test C continued
17. Why isn’t a lancelet considered a vertebrate?
_______________________________________________________________
_______________________________________________________________
_______________________________________________________________
CRITICAL THINKING
18. How is a butterfly’s development different from that of a hydra? Explain your
answer.
_______________________________________________________________
_______________________________________________________________
_______________________________________________________________
_______________________________________________________________
_______________________________________________________________
_______________________________________________________________
_______________________________________________________________
19. Describe the difference between an endoskeleton and an exoskeleton. How are
they alike? How are they different?
_______________________________________________________________
_______________________________________________________________
_______________________________________________________________
_______________________________________________________________
20. How do frogs and fish reproduce? Is this sexual or asexual reproduction?
Explain your answer.
_______________________________________________________________
_______________________________________________________________
_______________________________________________________________
_______________________________________________________________
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Introduction to Animals
Name ______________________________ Class __________________ Date __________________
Chapter Test C continued
CONCEPT MAPPING
21. Use the following terms to complete the concept map below:
sponge
bird
asymmetrical
vertebrates
feathers
flight
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Holt California Life Science
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Introduction to Animals
TEACHER RESOURCES
Assessment
Performance-Based Assessment
Teacher Notes
PURPOSE
Students examine the differences between down and contour feathers and make a
connection between structure and function.
TIME REQUIRED
One 45-minute class period. Students will need 25 minutes at the activity station
and 20 minutes to answer the analysis questions.
RATING
Teacher Prep–1
Student Set-Up–1
Concept Level–1
Clean Up–1
ADVANCE PREPARATION
Equip each activity station with the necessary materials. Be sure the down is not
cooler than room temperature—this will affect the results.
SAFETY CAUTION
Spilled water is a slipping hazard. Wipe up spills immediately. Hot water is a burn
hazard. Have students use caution when running hot water over the milk
container. Ask students if anyone is allergic to feathers. Goggles should be worn
while handling glassware.
TEACHING STRATEGIES
This activity works best in groups of 2–3 students. Students should know the
names of the parts of a feather before starting the activity: shaft, barb, and barbule.
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Introduction to Animals
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Performance-Based Assessment continued
Evaluation Strategies
Use the following rubric to help evaluate student performance.
Rubric for Assessment
Possible
points
Appropriate use of materials and equipment
(10 points possible)
10–8
Successful completion of activity; safe and careful handling of
materials and equipment; precise measurements; superior lab skills
7–5
Generally complete activity; acceptable handling of materials and
equipment; somewhat precise measurements; average lab skills
4–1
Incomplete activity; unsafe handling of materials and equipment;
imprecise measurements; apparent lack of skill
Quality and clarity of observations
(40 points possible)
40–28
Superior observations stated clearly and accurately; high level
of detail
27–15
Accurate observations; moderate level of detail
14–1
Erroneous, incomplete, or unclear observations; little or no detail
Explanation of observations
(50 points possible)
50–35
Clear, detailed explanation; superior knowledge of the functions of
different types of feathers; use of examples to support explanation
34–20
Somewhat unclear explanation; adequate understanding of the
functions of different types of feathers; minor difficulty in expression
19–1
Unclear or irrelevant explanation; poor understanding of the
functions of different types of feathers; substantial factual errors
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Holt California Life Science
91
Introduction to Animals
Name ______________________________ Class __________________ Date __________________
Assessment
SKILLS PRACTICE
Performance-Based Assessment
OBJECTIVE
All birds have two types of feathers that have different functions. In this activity
you will examine these two feather types and demonstrate their differences.
KNOW THE SCORE!
As you work through the activity, keep in mind that you will be earning a grade
for the following:
• how well you work with the materials and equipment (10%)
• the quality and clarity of your observations (40%)
• how well you analyze your observations (50%)
MATERIALS AND EQUIPMENT
•
•
•
•
• pillow, down
• thermometer
• water, hot
cans, aluminum (2)
clock or watch
foil, aluminum
graduated cylinder
SAFETY INFORMATION
• Wipe up spills
slipping hazard.
immediately; spilled water is a
PROCEDURE
1. Pour 250 mL of hot water into each aluminum can. Measure the temperature of the water
in each can. Record the temperatures.
_______________________________________________________________
_______________________________________________________________
2. Cover the tops of the cans with aluminum foil. Put one can aside, and cover the other one
completely with the pillow, being careful not to spill the water. After 15 minutes,
measure the temperature of the water in each can. What are the temperatures now?
_______________________________________________________________
_______________________________________________________________
_______________________________________________________________
_______________________________________________________________
_______________________________________________________________
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Introduction to Animals
Name ______________________________ Class __________________ Date __________________
Performance-Based Assessment continued
ANALYSIS
3. How did the down feathers affect the temperature of the water?
_______________________________________________________________
_______________________________________________________________
_______________________________________________________________
4. Examine the illustrations of the feathers below. Why do you think that the
feathers are structured differently?
_______________________________________________________________
_______________________________________________________________
_______________________________________________________________
BIG IDEA QUESTION
5. Describe how the structure of each feather part affects the feather’s function.
_______________________________________________________________
_______________________________________________________________
_______________________________________________________________
_______________________________________________________________
_______________________________________________________________
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Holt California Life Science
93
Introduction to Animals
TEACHER RESOURCES
Assessment
Standards Assessment
Teacher Notes and Answer Key
To provide practice under more realistic testing conditions, give students 20 min to answer all
of the questions in this assessment.
QUESTION NUMBER
1
CORRECT ANSWER
D
STANDARD
7.1.f (mastering)
2
A
7.2.a (supporting)
3
B
7.5.b (supporting)
4
C
7.5.c (supporting)
5
C
7.5.a (supporting)
6
C
7.2.a (mastering)
7
D
7.5.a (mastering)
8
B
7.5.g (mastering)
9
C
10
A
11
A
7.5.c (supporting)
7.5.a (supporting)
7.5.g (exceeding)
7.1.f (mastering)
12
D
7.2.a (mastering)
13
A
7.5.a (supporting)
14
B
7.1.c (mastering)
15
D
7.1.a (mastering)
16
A
7.3.d (mastering)
17
A
6.5.c (mastering)
TEST DOCTOR
The following Standards Assesment questions have been diagnosed by the Test Doctor. Find out what
might be causing your students’ “ailing” answers. Each Test Doctor is followed by a diagnostic
teaching tip to help you address students’ learning needs.
Question 1 asks students to define differentiate in context.
A
B
C
D
Incorrect. Differentiate does not mean “to see or show the difference between” in this sentence.
Incorrect. In this sentence, differentiate does not mean “to multiply more rapidly.”
Incorrect. Differentiate in this sentence does not mean “to calculate a mathematical function.”
Correct. When cells differentiate, they become specialized for specific functions.
Diagnostic Teaching Tip: Students who have difficulty answering this question correctly
might benefit from practice using words with multiple definitions in context. Have students use
the dictionary to find a word with at least three meanings. Instruct them to write three sentences,
each using a different definition of the word. Collect the sentences and divide students into
teams. Read definitions aloud, and then read a sentence and have teams compete to identify the
correct definition of the word.
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Introduction to Animals
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Standards Assessment continued
Question 2 asks students to match words that have similar meanings.
A Correct. Methods and ways are similar in meaning because they both mean
“means or manners of doing or achieving goals.”
B Incorrect. Actions are movements or series of movements. While methods
involve actions, the two words do not have similar meanings.
C Incorrect. Orders are commands or directions. Methods are ways of doing
things. These words do not have similar meanings.
D Incorrect. Sets are groups of similar things. Methods are ways of doing things.
These words do not have similar meanings.
Diagnostic Teaching Tip: Students who have difficulty answering this
question correctly might benefit from practice matching words with similar
meanings. Create a crossword puzzle with one-word clues whose answers
are their synonyms.
Question 3 asks students to define a word in context.
A Incorrect. “Move emotionally” is not what affect means in this sentence.
B Correct. In this sentence, affect means “act upon or have an effect upon.” The
failure of an organ can act upon or have an effect upon the entire organ
system.
C Incorrect. Affect does not mean “infect or damage with disease” in this
sentence.
D Incorrect. In this sentence, affect does not mean “assume a particular form.”
Diagnostic Teaching Tip: Students who struggle to answer this item
correctly may benefit from practicing using terms, such as affect. Have
students write three sentences in which they correctly use different forms of
affect.
Question 4 asks students to correctly match a word with the given definition.
A Incorrect. Construction means “a structure that has been built.” A construction
does not necessarily provide support for something.
B Incorrect. A house is a particular kind of structure, but its purpose is not to
support something.
C Correct. A framework is a structure for supporting something. The bones and
muscles provide a framework that makes movement possible.
D Incorrect. Plane means “a flat or level material surface,” or a tool that is used to
make level or flatten a piece of wood.
Diagnostic Teaching Tip: Students who have difficulty answering this
question correctly might benefit from practice differentiating between
related terms. Have students in groups take turns reading definitions aloud
from the dictionary while other students in the group write down a word to
match the definition. The reader should write down the correct word then
read all the words aloud so that members of the group can vote on which
word they think matches the definition.
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Introduction to Animals
TEACHER RESOURCES
Standards Assessment continued
Question 5 asks students to choose the correct part of speech for a sentence.
A Incorrect. Individually is an adverb. This sentence needs an adjective to modify cells,
tissues, and organs.
B Incorrect. Individuate is a verb. This sentence already has a verb: function.
C Correct. Organ systems function with the help of individual cells, tissues, and organs.
The sentence was missing an adjective, and individual is an adjective.
D Incorrect. Individualize is a verb. This sentence needs an adjective to modify cells,
tissues, and organs.
Students who have difficulty answering this question
correctly might benefit from a review of the parts of speech. Have students write a
short story in which different parts of speech have been replaced with blanks.
Instruct students to write the names of the missing parts of speech beneath each
blank then have a partner complete the story.
Diagnostic Teaching Tip:
Question 6 asks students to demonstrate knowledge of the differences between sexual and
asexual reproduction.
A Incorrect. A monotreme is a type of mammal that lays shelled eggs. Mammals
reproduce sexually.
B Incorrect. Segmentation is not a method of reproduction. Segmentation is a description
of the bodies of many animals that are segmented, or divided into sections.
C Correct. Budding is a form of asexual reproduction during which a part of an organism
develops into a new organism and then drops off the parent. The offspring of asexual
reproduction are identical to the parent organism.
D Incorrect. Metamorphosis is not a method of reproduction. It is a process of
development for both invertebrates and vertebrates by which they develop from egg to
adulthood.
Students who have difficulty answering this question
correctly might benefit from reviewing the two kinds of asexual reproduction. Have
students do library and Internet research to create a list of animals that reproduce
asexually. Have students create a graphic organizer to sort animals that reproduce
by budding and those that reproduce by fragmentation.
Diagnostic Teaching Tip:
Question 7 asks students to demonstrate knowledge of the organ systems in animals.
A Incorrect. The respiratory system helps an animal breathe. While animals can breathe
through their mouths, the stomach, intestine, and anus do not help with breathing.
B Incorrect. The nervous system is specialized for receiving and sending electrical
signals. The organs shown in the image do not help with these functions.
C Incorrect. The circulatory system moves oxygen, carbon dioxide, and nutrients around
the body in the blood. The mouth, stomach, intestine, and anus are not organs
specialized to move blood.
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Introduction to Animals
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Standards Assessment continued
D Correct. The digestive system of the snail includes the mouth, the stomach, the
intestine, and the anus. The organs of the digestive system are specialized to
break down food (mouth and stomach), absorb its nutrients (stomach and
intestine), and expel waste from the body (anus).
Diagnostic Teaching Tip: Students who have difficulty answering this
question might benefit from labeling several different organ systems in
different organisms. Create a worksheet containing simplified diagrams of
the respiratory, circulatory, digestive, and nervous systems in different
animals. Have students label the organs in the system and describe how the
system functions to help the animal survive.
Question 8 asks students to demonstrate understanding of how sensory organs
function.
A Incorrect. The specialized cells in a dragonfly’s eyes are not directly connected
to the dragonfly’s wings, nor do dragonflies have bones.
B Correct. The brain interprets the signals it receives from the eyes as an image.
The brain then signals the body as to how and where to fly to get its prey.
Dragonflies have very large compound eyes with many lenses. Their keen
eyesight and strong wings make them fine hunters.
C Incorrect. Dragonflies do not have receptors on the surface of their eyes.
D Incorrect. The nerve cells in a dragonfly’s eyes cannot interpret any signals.
Nerves are only able to transmit signals.
Diagnostic Teaching Tip: Students who have difficulty answering this
question correctly might benefit from reviewing how the structures of the
eye help animals see. Show students a diagram or photo of the human eye or
the eye of a vertebrate. Discuss how the lens, pupil, and retina function.
Compare this image with that of an insect’s compound eye. Discuss how the
number of lenses might affect the way an insect sees compared to the way a
human or other vertebrate sees.
Question 9 asks students to demonstrate understanding of the difference between
invertebrates and vertebrates.
A Incorrect. Vertebrates actually have endoskeletons, which are bones that create
a framework inside the body. Invertebrate bodies are supported and protected in
other ways. Some but not all have exoskeletons, which are hard outer
coverings.
B Incorrect. Invertebrates reproduce sexually and asexually. Most vertebrates
reproduce sexually.
C Correct. Vertebrates have bony structures called vertebrae that make up the
backbone of their endoskeleton. Invertebrates do not have backbones.
D Incorrect. Invertebrates may have bilateral, radial, or asymmetrical body plans.
All vertebrates have bilateral symmetry.
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Introduction to Animals
TEACHER RESOURCES
Standards Assessment continued
Diagnostic Teaching Tip: Students who have difficulty answering this
question correctly might benefit from reviewing the similarities and differences
between invertebrates and vertebrates. Have students create a graphic organizer
that includes the seven characteristics of animals. Instruct them to fill in each
category for invertebrates and vertebrates, citing examples for each.
Question 10 asks students to demonstrate understanding of body structure in
animals.
A Correct. The sea urchin’s body has radial symmetry, meaning its body is
organized around a center, like spokes on a wheel. Animals with radial
symmetry do not have heads.
B Incorrect. Skeletal is not a type of body plan.
C Incorrect. The sea urchin is not bilateral. An organism that has bilateral
symmetry can be divided into two equal parts. The two sides of its body mirror
each other.
D Incorrect. The sea star does not have an asymmetrical body plan. An
asymmetrical body cannot be divided into two or more equal parts and is not
organized around a center.
Diagnostic Teaching Tip: Students who have difficulty answering this
question correctly might benefit from reviewing the meanings of the words
bilateral, radial, and asymmetrical. Divide students into groups of three and assign
one word to each student to define and illustrate. Have students present their
definitions to each other in their groups.
Question 11 asks students to demonstrate knowledge that cells in animals begin
differentiating while the organism is still an embryo.
A Correct. As an embryo grows, its cells become specialized to perform different
functions. These specialized cells group to form tissues, organs, and organ
systems that will help the animal grow and survive.
B Incorrect. Although vertebrates develop many similar structures as they
develop, not all vertebrates develop fins before becoming adults.
C Incorrect. Cell differentiation begins in a developing embryo, and does not
occur only after birth.
D Incorrect. Early embryos of different species actually look more like each other
than the adults of their own species. As they mature, embryos look more like
the adults of their own species.
Diagnostic Teaching Tip: Students who have difficulty answering this
question correctly might benefit from comparing the stages of development in
invertebrates and vertebrates. Have students write paragraphs describing the
development of an animal without identifying which animal it is. Invite students to
read their descriptions aloud so that other students can guess whether the animal is
an invertebrate or a vertebrate. If the classification cannot be guessed from the
details of the animal’s development, have students provide other clues as to what
type of animal it is.
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Introduction to Animals
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Standards Assessment continued
Question 12 asks students to demonstrate understanding of sexual reproduction.
A Incorrect. Fertilization does not take place until the sperm and egg cells come
together.
B Incorrect. Fertilization does not take place in this scenario, which describes a
type of asexual reproduction called fragmentation.
C Incorrect. Fertilization takes place before cell differentiation can begin.
D Correct. Fertilization takes place when the nucleus of an egg cell fuses with the
nucleus of a sperm cell.
Diagnostic Teaching Tip: Students who have difficulty answering this
question correctly might benefit from matching specific animals with their
methods of reproduction. Have each student create three flashcards of
animals of particular interest to them. On one side of the card, students
should draw a diagram of the animal. On the other side, they should write
information about the seven characteristics all animals share. Have students
put their cards together to create a study pack for the classroom.
Question 13 asks students to demonstrate ability to understand labeled diagrams.
A Correct. The thorax is the middle segment of the lobster’s body. The bodies of
many lobsters are segmented into three parts: the head, the thorax, and the
abdomen.
B Incorrect. The abdomen is the back segment of the lobster’s body.
C Incorrect. The head is located at the front of the lobster’s body.
D Incorrect. The nerves are not a segment of a lobster’s body but rather a network
of pathways inside the body.
Diagnostic Teaching Tip: Students who have difficulty answering this
question correctly might benefit from additional practice creating and
labeling diagrams of animal anatomy. Have students choose an arthropod,
amphibian, or other animal of interest, and instruct them to create a detailed
diagram of the segmentation in the bodies of those organisms using colored
pencils.
Question 14 asks students to demonstrate knowledge that DNA is located in the
nucleus of a eukaryotic cell.
A Incorrect. Many animals live in the water and not just on land.
B Correct. Animals are eukaryotes, means that animals have eukaryotic cells. A
eukaryotic cell contains a nucleus in which the DNA is located.
C Incorrect. Some animals do not have circulatory systems, and some animals
have open circulatory systems. Therefore, not all animals have closed
circulatory systems.
D Incorrect. Not all animals have body cavities that surround and protect organs,
which are also called coeloms.
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Introduction to Animals
TEACHER RESOURCES
Standards Assessment continued
Diagnostic Teaching Tip: Students who have difficulty answering this
question correctly might benefit from reviewing the structure of different
types of cells. Have students create diagrams of an animal cell, a singlecelled organism, and a plant cell.
Question 15 asks students to demonstrate understanding that cells function
similarly in all organisms.
A Incorrect. The similar appearance of these structures is not an example of cells
functioning similarly in different animals.
B Incorrect. Having different coverings is not an example of cells functioning
similarly in different animals.
C Incorrect. The changing body form of the sea anemone is not an example of
cells functioning similarly in different animals.
D Correct. Nerve cells carrying impulses throughout the body in both a tortoise
and a chicken is an example of cells functioning similarly in different animals.
Diagnostic Teaching Tip: Students who have difficulty answering this
question correctly might benefit from reviewing the functions of tissues,
organs, and systems in different organisms. Display diagrams of body
systems in different animals and have students discuss their similarities and
differences. If possible, have students compare similar cells from different
organisms under a microscope.
Question 16 asks students to identify the role of an organism in the food web.
A Correct. Earthworms are decomposers, which means that earthworms get
energy from breaking down dead organisms. Earthworms release nutrients into
the soil through their waste products. Other organisms are able to take up these
nutrients for their own growth and survival.
B Incorrect. Not all consumers break down dead organisms; therefore, this is not
the most accurate answer for this item.
C Incorrect. Producers are organisms such as plants that can make their own food
through photosynthesis. Earthworms are not producers.
D Incorrect. Scavengers eat waste, leftovers from other consumers, and dead plant
and animal material, but they are not responsible for breaking down dead
organisms. Therefore, earthworms are not scavengers.
Diagnostic Teaching Tip: Students who have difficulty answering this
question correctly might benefit from reviewing the roles of different
organisms in food webs. Have students create a diagram of a food web using
plant and animal life from a community that interests them.
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100
Introduction to Animals
TEACHER RESOURCES
Standards Assessment continued
Question 17 asks students to demonstrate understanding of the characteristics of
the organisms grouped in the animal kingdom.
A Correct. Only organisms in the animal kingdom have bones; therefore, a fossil
of an organism that had bones would be correctly classified into the animal
kingdom.
B Incorrect. Members of the animal kingdom do not have cell walls around their
cells; therefore, a fossil that was classified into the animal kingdom would not
have this characteristic.
C Incorrect. All the members of the animal kingdom are multicellular organisms;
therefore, a single-celled organism would not be classified into the animal
kingdom.
D Incorrect. Members of the animal kingdom do not have root structures;
therefore, a fossil that was classified into the animal kingdom would not have
this characteristic.
Diagnostic Teaching Tip: Students who have difficulty answering this
question correctly might benefit from reviewing the characteristics of the
members of different levels of scientific classification. In pairs, have each
student write the characteristics of the members of each of the three domains
and the four kingdoms within the domain Eukarya on index cards. Then
have students switch these cards with their partner and identify the domain
or group name based on the characteristics that have been listed for that
group.
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Holt California Life Science
101
Introduction to Animals
Name ______________________________ Class __________________ Date __________________
Assessment
Standards Assessment
REVIEWING ACADEMIC VOCABULARY
_____ 1. In the sentence “As multicellular organisms develop, their cells differentiate
into specialized cells,” what does the word differentiate mean?
A to see or show the difference between
B to multiply more rapidly
C to calculate a mathematical function
D to become specialized for specific functions
_____ 2. Which of the following words is closest in meaning to the word methods?
A ways
B actions
C orders
D sets
_____ 3. In the sentence “The failure of an organ can affect the entire organ system,”
what does the word affect mean?
A move emotionally
B act upon or have an effect upon
C infect or damage with disease
D assume a particular form
_____ 4. Which of the following words means “a structure for supporting something”?
A construction
B house
C framework
D plane
_____ 5. Choose the appropriate form of the word for the following sentence: Organ
systems are made up of ______________________ cells, tissues, and organs.
A individually
B individuate
C individual
D individualize
REVIEWING CONCEPTS
_____ 6. Which of the following is a method of asexual reproduction?
A monotreme
B budding
C segmentation
D metamorphosis
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102
Introduction to Animals
Name ______________________________ Class __________________ Date __________________
Standards Assessment continued
_____ 7. In the image of the snail above, which organ system is shown?
A the respiratory system
B the nervous system
C the circulatory system
D the digestive system
_____ 8. How do the eyes of a dragonfly help the dragonfly catch its prey?
A Specialized cells in the eyes send signals to the bones in the dragonfly’s
wings.
B The brain interprets the signals sent by the dragonfly’s eyes as images to
identify the location of the prey.
C The dragonfly’s eyes have receptors on their surface to locate the prey.
D The nerve cells in the dragonfly’s eyes interpret the location of the prey.
_____ 9. Which of the following is a difference between invertebrates and vertebrates?
A Vertebrates have exoskeletons, and invertebrates have endoskeletons.
B Invertebrates reproduce only asexually, and vertebrates reproduce only
sexually.
C Vertebrates have a backbone, while invertebrates do not.
D Invertebrates have bilateral symmetry, while vertebrates have radial
symmetry.
_____ 10. What type of body symmetry does a sea urchin have?
A radial
B skeletal
C bilateral
D asymmetrical
_____ 11. Which of the following statements about vertebrate embryos is true?
A As embryos develop, their cells become specialized to perform different
functions.
B All vertebrate embryos develop fins before becoming adults.
C Cell differentiation occurs only after the birth of a vertebrate.
D Even as embryos, vertebrates look much like the adults of the species.
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Introduction to Animals
Name ______________________________ Class __________________ Date __________________
Standards Assessment continued
_____ 12. Most vertebrates reproduce sexually. When does fertilization occur in
sexual reproduction?
A when a male animal releases sperm and a female animal releases
eggs
B when part of an organism breaks off and begins to grow
independently
C when the cells of the embryo begin to differentiate and become
specialized
D when the nucleus of a sperm cell fuses with the nucleus of an egg
cell
_____ 13. In the diagram of a lobster shown above, which segment of the
lobster’s body is labeled B?
A the thorax
B the abdomen
C the head
D the nerves
REVIEWING PRIOR LEARNING
_____ 14. What does the statement “All animals are eukaryotes,” mean?
A It means that all animals live on land.
B It means that all of the DNA of an animal is located in the nuclei of
the cells of the animal.
C It means that all animals have closed circulatory systems.
D It means that all animal bodies have coeloms.
_____ 15. Which of the following is an example of similar cell function in
different animals?
A The wings of a bat and the flippers of a dolphin look similar.
B Animals have a variety of coverings, including skin, scales, and fur.
C Sea anemone larvae have medusa body forms but are polyps as
adults.
D Nerve cells carry impulses throughout the body in both a tortoise
and a chicken.
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content are the responsibility of the instructor.
Holt California Life Science
104
Introduction to Animals
Name ______________________________ Class __________________ Date __________________
Standards Assessment continued
_____ 16. What role does an earthworm play in the transfer of energy in the food
web of an ecosystem?
A decomposer
B consumer
C producer
D scavenger
_____ 17. What characteristics might a fossil that was classified into the animal
kingdom have?
A The fossilized organism had bones.
B The fossilized organism had structures identified as cell walls.
C The fossil is of a single-celled organism.
D The fossilized organism had root structures.
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Holt California Life Science
105
Introduction to Animals
TEACHER RESOURCES
Explore Activity
DATASHEET
Observing Animal Characteristics
Teacher Notes
In this activity, students will choose tools to observe animals and make
connections between animals that look very different but have the same basic
needs (covers standards 7.5.a and 7.7.a).
MATERIALS
For each group
You will need to approve the tools each student selects.
SAFETY CAUTION
Remind students to review all safety cautions and icons before beginning this
activity. Tell students to exercise caution around wild or unfamiliar animals, and
remind students never to handle wild or unfamiliar animals.
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content are the responsibility of the instructor.
Holt California Life Science
106
Introduction to Animals
Name__________________________ Class____________ Date______________
Explore Activity
DATASHEET A
Observing Animal Characteristics
You don’t have to travel far to see interesting animals. If you look closely, you
can find many animals nearby. In this activity, you will observe the
characteristics of two different animals. Caution: Always be careful around
wild or unfamiliar animals, because they may bite or sting. Do not handle wild
animals or any animals that are unfamiliar to you.
SAFETY INFORMATION
PROCEDURE
1. Go outside.
 Find two different kinds of animals to observe.
2. Do not disturb the animals.
 Watch them quietly for a few minutes from a distance.
 You may want to use binoculars or a magnifying lens.
3. Write down everything that you notice about each animal.
 What is the name of each kind of animal?
 Where did you find them?
 What do they look like?
 How big are they?
 What are they doing?
 You may want to draw a picture of them.
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Observing Animal Characteristics continued
ANALYSIS
4. Compare the two animals that you studied.
 Do they look alike or different?
 Can you identify their body parts?
5. How do the animals move?
 What body parts are they using to help them move?
6. Can you tell what each animal eats?
 What parts of each animal help it find or catch food?
 Do the animals have any behaviors that help them find or catch food?
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Explore Activity
DATASHEET B
Observing Animal Characteristics
You don’t have to travel far to see interesting animals. If you look closely, you
can find many animals nearby. In this activity, you will observe the
characteristics of two different animals. Caution: Always be careful around
wild or unfamiliar animals, because they may bite or sting. Do not handle wild
animals or any animals that are unfamiliar to you.
SAFETY INFORMATION
PROCEDURE
1. Go outside, and find two different kinds of animals to observe.
2. Without disturbing the animals, watch them quietly for a few minutes from a
distance. You may want to use binoculars or a magnifying lens.
3. Write down everything that you notice about each animal. Do you know what
kind of animal each is? Where did you find them? What do they look like?
What are they doing? You may want to draw a picture of them.
ANALYSIS
4. Compare the two animals that you studied. Do they look alike? Identify their
body parts.
5. How do the animals move? What structures are they using to help them move?
6. Can you tell what each animal eats? What characteristics of each animal help
it find or catch food?
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Explore Activity
DATASHEET C
Observing Animal Characteristics
You don’t have to travel far to see interesting animals. If you look closely, you
can find many animals nearby. In this activity, you will observe the
characteristics of two different animals. Caution: Always be careful around
wild or unfamiliar animals, because they may bite or sting. Do not handle wild
animals or any animals that are unfamiliar to you.
SAFETY INFORMATION
PROCEDURE
1. Go outside, and find two different kinds of animals to observe.
2. Without disturbing the animals, watch them quietly for a few minutes from a
distance. You may want to use binoculars or a magnifying lens.
3. Write down your observation of the animal. Question to consider: Do you
know what kind of animal each is? Where did you find them? What do they
look like? What are they doing? You may want to draw a picture of them.
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Introduction to Animals
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Observing Animal Characteristics continued
ANALYSIS
4. a. Compare the two animals that you studied. Do they look alike? Identify
their body parts.
b. How can you tell that the animals you observed are really animals and not
other organisms?
5. Describe how the animals move and the structures they use to help them move.
6. Describe what each animal eats and the structures or behaviors that each
animal uses to help it find or catch food.
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Introduction to Animals
TEACHER RESOURCES
Quick Lab
DATASHEET
Differentiating Blood Cells
Teacher Notes
In this activity, students explore the different structures of red blood cells and
white blood cells as the result of differentiation (covers standard 7.1.f). Explain to
students that all blood cells form from a special type of cell called a hematopoietic
stem cell.
MATERIALS
For each group
• flip book animation
• red bone marrow smear
• slide
SAFETY CAUTION
Remind students to review all safety cautions and icons before beginning this
activity.
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Quick Lab
DATASHEET A
Differentiating Blood Cells
SAFETY INFORMATION
PROCEDURE
1. Get a microscope and the slide of the red bone marrow smear.
 Follow your teacher’s directions on how to set up and operate a microscope.
 Examine the slide of the red bone marrow smear with the microscope.
 Start at the lowest power first.
 When you can see the cells under the lower-powered lens, switch to a
higher-powered lens.
2. Notice the different kinds of blood cells in the smear.
 Red blood cells appear rounded and concave, like a doughnut.
 White blood cells are larger and irregularly shaped.
 Sketch a red blood cell and a white blood cell below.
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Differentiating Blood Cells continued
3. All blood cells differentiate from the same kind of cell called a blood stem
cell.
 Examine the sketch of a blood stem cell made by your teacher.
 Describe how the blood stem cell differs from the red and white blood cells.
4. Choose either the red blood cell or white blood cell.
 Make a flip book animation that shows how the cell developed from the
blood stem cell.
 Start with a sketch of the blood stem cell.
 Make several sketches of what the blood cell might look like as it changes
into a red or white blood cell.
 End with a red or white blood cell.
 Staple the sketches together to make the flip book.
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Quick Lab
DATASHEET B
Differentiating Blood Cells
SAFETY INFORMATION
PROCEDURE
1. Examine the slide of the red bone marrow smear.
2. Notice the different kinds of blood cells in the smear. Sketch a red blood cell
and a white blood cell.
3. All blood cells differentiate from the same kind of cell called a blood stem
cell. Examine the sketch of a blood stem cell made by your teacher.
4. Make a flip book animation that shows how one of the blood cells that you
sketched developed from the blood stem cell.
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Quick Lab
DATASHEET C
Differentiating Blood Cells
SAFETY INFORMATION
PROCEDURE
1. Examine the slide of the red bone marrow smear.
2. Notice the different kinds of blood cells in the smear. Describe how the cells
differ. Sketch a red blood cell and a white blood cell.
3. All blood cells differentiate from the same kind of cell called a blood stem
cell. Examine the sketch of a blood stem cell made by your teacher. Describe
how the blood stem cell differs from the red and white blood cells.
4. Make a flip book animation that shows how one of the blood cells that you
sketched developed from the blood stem cell.
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TEACHER RESOURCES
Quick Lab
DATASHEET
Grouping Organisms by Characteristics
Teacher Notes
In this activity, students classify organisms based on the organisms’
characteristics (covers standard 7.5.a). Discuss with the class how observable
characteristics are a product of an organism’s levels of structural organization.
When compiling the initial list, students should select a diversity of animals.
MATERIALS
For each group
• sheet of paper
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Introduction to Animals
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Quick Lab
DATASHEET A
Grouping Organisms by Characteristics
PROCEDURE
1. On a sheet of paper, write a list of six organisms described in this chapter.
2. Choose a characteristic and divide the organisms into two groups based on
this characteristic.

Possible characteristics include presence of a backbone, number of
body segments, type of body symmetry, body coverings, and method of
reproduction.

Record the animals in each group.
3. Choose a different characteristic and divide each group in step 2 into two
new groups.

Keep a record of the animals in each group.
4. Do step 3 again until there is only one animal in each group.
5. Exchange your list with another student.

Try to guess what characteristics the other student used to divide his or
her list of organisms.

Ask the student if the characteristics you guessed are right.
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Quick Lab
DATASHEET B
Grouping Organisms by Characteristics
PROCEDURE
1. On a sheet of paper, write a list of six organisms from this chapter.
2. Divide the organisms into two groups based on one characteristic. Record the
animals in each group.
3. Divide each group into two new groups based on a different characteristic.
Keep a record of the animals in each group.
4. Repeat step 3 until there is only one animal in a group.
5. Exchange your list with another student, and try to figure out the
characteristics the student used to divide his or her list of organisms.
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Quick Lab
DATASHEET C
Grouping Organisms by Characteristics
PROCEDURE
1. On a sheet of paper, write a list of six organisms from this chapter.
2. Divide the organisms into two groups based on one characteristic. Record the
animals in each group.
3. Divide each group into two new groups based on a different characteristic.
Keep a record of the animals in each group.
4. Repeat step 3 until there is only one animal in a group. Explain why you
chose these characteristics to divide your list of animals.
5. Exchange your list with another student, and try to figure out the
characteristics the student used to divide his or her list of organisms. Do you
think the characteristics he or she used to divide his or her list are logical?
Explain your answer.
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TEACHER RESOURCES
Quick Lab
DATASHEET
Seeing Like an Insect
Teacher Notes
In this activity, students explore how insects see images (covers standard 7.5.g).
Emphasize that the eyes need light for sight. When light enters the eye, signals are
transmitted to the brain. The brain then interprets these signals as an image.
MATERIALS
For each group
• grid
• marker, black
• paper, tracing
• ruler
• tape
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Introduction to Animals
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Quick Lab
DATASHEET A
Seeing Like an Insect
Insects have a compound eye made up of repeating units. Each unit has its
own lens.
TRY IT!
1. Use a ruler to draw a grid on a sheet of tracing paper.
 The grid should be about 10 cm by 10 cm.
 The grid lines should be 0.5 cm apart.
2. Place the grid over a black-and-white image.
 Secure the grid with tape.
3. Note the relative amount of black ink that shows through in each grid box.
4. Use a black marker to fill in the grid boxes that are on top of an area that is
mostly black.
 Don’t fill in the grid boxes that are above squares that are mostly white.
THINK ABOUT IT!
5. Remove your grid, and look at it from across the room.
 What do you see?
6. Complete this sentence: In this activity, the repeating units in the insect eye are
mimicked by the_____.
7. An insect’s eye is curved. How might the curve of the insect’s eye change the
images an insect sees?
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Quick Lab
DATASHEET B
Seeing Like an Insect
Insects have a compound eye made up of repeating units. Each unit has
its own lens.
TRY IT!
1. Use a ruler to draw a grid with dimensions of about 10 cm by 10 cm on a
sheet of tracing paper. The grid lines should be separated by 0.5 cm.
2. Place the grid over a black-and-white image. Secure the grid with tape.
3. Note the relative amount of black ink that shows through in each box.
4. Use a black marker to fill in the grid boxes that are on top of an area that is
mostly black. Don’t fill in the grid boxes that are above squares that are mostly
white.
THINK ABOUT IT!
5. Remove your grid, and examine it from across the room. Describe what you
see.
6. What part of the activity mimicked the repeating units in the eye of an insect?
7. How might the curve of the insect eye further change how an insect sees
images?
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Introduction to Animals
Name__________________________ Class____________ Date______________
Quick Lab
DATASHEET C
Seeing Like an Insect
Insects have a compound eye made up of repeating units. Each unit has
its own lens.
TRY IT!
1. Use a ruler to draw a grid with dimensions of about 10 cm × 10 cm on a sheet
of tracing paper. The grid lines should be separated by 0.5 cm.
2. Place the grid over a black-and-white image. Secure the grid with tape.
3. Note the relative amount of black ink that shows through in each box.
4. Use a black marker to fill in the grid boxes that are on top of an area that is
mostly black. Don’t fill in the grid boxes that are above squares that are mostly
white.
THINK ABOUT IT!
5. Remove your grid, and examine it from across the room. Describe what you
see.
6. How does this activity illustrate the vision of an insect?
7. Describe how the curve of the insect eye might affect how an insect sees
images.
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TEACHER RESOURCES
Quick Lab
DATASHEET
Amplifying Sound
Teacher Notes
In this activity, students will experiment with characteristics that affect hearing
(covers standard 7.5.g). The large opening of ear trumpets captures sound waves
and “funnels” them to the smaller end of the tube. There, the sound waves exit the
tube and enter the ear.
MATERIALS
For each student
• funnel
• paper
• tape
SAFETY CAUTION
Remind students to review all safety cautions and icons before beginning this
activity.
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Quick Lab
DATASHEET A
Amplifying Sound
SAFETY INFORMATION
PROCEDURE
1. Roll a sheet of paper into a loose cone.
2. Wrap the smaller open end of the cone around the stem of a funnel.
 Use tape to secure the shape of the cone.
3. Place the funnel over your ear.
4. Move the cone toward a faint sound.
 Then move the cone away from the sound.
 When is the sound loudest? Is it loudest when the cone is positioned directly
toward the sound or away from the sound?
5. Make a new cone with several sheets of paper so that the cone is larger.
 Repeat step 4.
 Is the sound clearer and easier to hear with the larger or smaller cone?
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Quick Lab
DATASHEET B
Amplifying Sound
SAFETY INFORMATION
PROCEDURE
1. Roll a sheet of paper into a loose cone.
2. Wrap the smaller open end of the cone around the stem of a funnel. Use tape
to secure the shape of the cone.
3. Place the funnel over an ear.
4. Move the cone toward a faint sound and then away from the sound. How
does the sound change?
5. Make a new cone with several sheets of paper. Repeat step 4. How does the
size of the cone affect what you hear?
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Quick Lab
DATASHEET C
Amplifying Sound
SAFETY INFORMATION
PROCEDURE
1. Roll a sheet of paper into a loose cone.
2. Wrap the smaller open end of the cone around the stem of a funnel. Use tape
to secure the shape of the cone.
3. Place the funnel over an ear.
4. Move the cone toward a faint sound and then away from the sound. Describe
how the sound changes as you move the cone.
5. Make a new cone with several sheets of paper. Repeat step 4. Describe how
changes to the cone affect what you hear.
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TEACHER RESOURCES
Skills Practice Lab
DATASHEET
Structure and Function of Bone
Teacher Notes
In this lab, students will identify and compare the
densities of three kinds of animal bones. This activity
will help students understand how a bone’s density is
related to its function (covers standards 7.5.a and 7.5.c).
In this lab, students will also consider the suitability of
the equipment needed to conduct the activity (covers
standard 7.7.a).
TIME REQUIRED
One 45-minute class period
LAB RATINGS
Teacher Prep–4
Student Set-Up–2
Concept Level–3
Clean Up–1
MATERIALS
The materials listed on the student page are enough for two students.
SAFETY CAUTION
Remind students to review all safety cautions and icons before beginning this lab
activity. Students should use caution when working with a length of stiff wire.
PREPARATION NOTES
Collect and prepare sets of bone samples in advance. Once classroom sets are
prepared, they can be easily stored and reused. For the chicken bone, leg bones
will work best. For the fish bone, try to obtain three to four connected vertebrae of
a swordfish or large tuna. For added safety, make sure that the spines are cut off.
For the beef bone, marrow bones or broad sections of beef, lamb, or pork bone
will all work well. Prepared beef bones sold as chew toys for dogs will also work.
Make sure that the bones will fit into the graduated cylinder that students will use.
To prepare the bones, boil them in water. As they cook, the muscle and other
soft tissues will loosen. Let the bones cool, and use a knife to scrape off any
leftover tissue. Boil the bones again. After they cool, scrape off any remaining
meat. If you dry the bones outdoors, make sure that pets or other animals will not
find them.
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Introduction to Animals
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Skills Practice Lab
DATASHEET A
Structure and Function of Bone
The structure of each body part of an organism is related to the function of that
body part. For example, animals depend on specialized body parts for movement.
Animals contract and relax muscles that are attached to bones in order to move.
Some animals have legs, wings, or fins to move around. In vertebrates, most
movement is the result of bones and muscles working together. Bones that support
a lot of weight are thick and heavy, such as in elephants. Bones that do not support
a lot of weight are light, such as in the wings of birds.
You have already learned that the bones of vertebrates have many similarities.
In this activity, you will compare the bones of a mammal, a bird, and a fish.
Through this activity, you will learn how differences in the structure of
different bones relate to the function of these bones.
OBJECTIVES
Determine the density of three kinds of animal bones.
Compare the bone of a mammal, a fish, and a bird.
Identify the relationship between the structure of the bone and the function of the
bone.
MATERIALS
 balance, laboratory
 beef bone
 chicken bone
 fish bone
 graduated cylinder, large
 string
 wire
SAFETY INFORMATION
Using Scientific Methods
ASK A QUESTION
1. After reading the information above, you may have many questions.
 Let’s ask, “Are the bones of animals that walk more dense than the bones
of animals that swim or of animals that fly?”
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Structure and Function of Bone continued
FORM A TESTABLE HYPOTHESIS
2. To change the question into a testable hypothesis, you should come up with a
possible answer to the question.
 A possible answer could be: “There are no differences in density between
the bones of animals that walk, swim, or fly.”
PROCEDURE
3. Use the table below to record the measurements for each kind of bone.
Bone Measurements
Kind of bone
Mass of
Volume of
Density of
bone (g)
bone (cm3)
bone (g/cm3)
Mammal bone
Chicken bone
Fish bone
4. Use a balance to find the mass of a mammal (beef) bone.
 Remember to set the balance to zero before you start.
 Record the mass of the bone in your table.
5. Fill a graduated cylinder about 3/4 full with water.
 Note the water level in the cylinder. (Note: 1 mL = 1 cm3 )
 Make sure to look at eye level when you read the volume.
 Read the volume at the bottom of the meniscus.
6. Tie a string around the beef bone.
 Gently lower it into the cylinder.
 When the bone is completely underwater, note the new water level.
7. Determine the volume of the bone.
 Subtract the initial water level in the graduated cylinder from the water
level once the bone was underwater.
 Record your finding in your table.
8. Calculate the density of this bone.
 Divide the bone’s mass by its volume.
 Record this value in grams per centimeter cubed (g/cm3) in your table.
9. Repeat steps 4–8 using a chicken bone and a fish bone.
 If a bone floats, use a length of stiff wire to hold it under the surface of the
water.
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Structure and Function of Bone continued
ANALYZE THE RESULTS
10. Analyzing Results Which bones sank?
 Which bones floated?
11. Evaluating Results Look at the densities in your table.
 Which bone was the most dense?
 Which bone was the least dense?
DRAW CONCLUSIONS
12. Drawing Conclusions Was there a difference in bone density in the three
types of bones?
 Does this evidence prove or disprove the hypothesis?
13. Applying Results Do you think heavy, dense bones would need large
muscles to move them?
14. Making Inferences Does the type of movement also affect the
characteristics of the muscles required to move these bones? (Hint: Compare
walking to flying.)
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Structure and Function of Bone continued
15. Making Inferences Most birds fly in the air, most mammals move on land,
and fish swim in the water.
 How is the density of the different bones related to how an organism
moves?
 How is the density of the different bones related to where an organism
lives?
16. Applying Conclusions A whale is a huge organism. In its natural
environment, much of the whale’s weight is supported by water.
 If an organism that was the size of a whale lived on land, what kind of
bones would the organism need to support its weight?
 What kind of muscles would the animal need to move those bones?
BIG IDEA QUESTION
17. Identifying Relationships Choose one of the animals from this experiment.
Describe how the structure of its bones is related to its life function.
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Skills Practice Lab
DATASHEET B
Structure and Function of Bone
The structure of each body part of an organism is related to the function of
that body part. For example, animals depend on specialized body parts for
movement. Animals contract and relax muscles that are attached to bones in
order to move. Some animals have legs, wings, or fins to move around. In
vertebrates, most movement is the result of bones and muscles working
together. Bones that support a lot of weight are thick and heavy, such as in
elephants. Bones that do not support a lot of weight are light, such as in the
wings of birds.
You have already learned that the bones of vertebrates have many
similarities. In this activity, you will compare the bones of a mammal, a bird,
and a fish. Through this activity, you will learn how differences in the
structure of different bones relate to the function of these bones.
OBJECTIVES
Determine the density of three kinds of animal bones.
Compare the bone of a mammal, a fish, and a bird.
Identify the relationship between the structure of the bone and the function of the
bone.
MATERIALS
 balance, laboratory
 beef bone
 chicken bone
 fish bone
 graduated cylinder, large
 string
 wire
SAFETY INFORMATION
Using Scientific Methods
ASK A QUESTION
1. Let’s ask, “Are the bones of animals that walk more dense than the bones of
animals that swim or of animals that fly?”
FORM A TESTABLE HYPOTHESIS
2. To change the question into a testable hypothesis, you should come up with
the following: “There are no differences in density between the bones of
animals that walk, swim, or fly.”
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Introduction to Animals
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Structure and Function of Bone continued
PROCEDURE
3. Use the table below to record the measurements for each kind of bone.
Bone Measurements
Kind of bone
Mass of
Volume of
Density of
bone (g)
bone (cm3)
bone (g/cm3)
Mammal bone
Chicken bone
Fish bone
4. Use a balance to determine the mass of a mammal bone. Record this value in
your table.
5. Fill a graduated cylinder about 3/4 full with water. Note the water level in the
cylinder. (Note: 1 mL = 1 cm3)
6. Tie a string around the beef bone. Gently lower it into the cylinder. When the
bone is completely submerged, note the new water level.
7. Determine the volume of the bone, by subtracting the initial water level in the
graduated cylinder from the water level when the bone was submerged.
Record your finding in your table.
8. Calculate the density of this bone by dividing the bone’s mass by its volume.
Record this value in grams per centimeter cubed (g/cm3) in your table.
9. Repeat steps 4–8 using a chicken bone and a fish bone. If a bone floats, you
will need to hold it under the surface of the water by using a length of wire.
ANALYZE THE RESULTS
10. Analyzing Results Which bones sank? Which bones floated?
11. Evaluating Results Which bone was the most dense? Which bone was the
least dense?
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Structure and Function of Bone continued
DRAW CONCLUSIONS
12. Drawing Conclusions Did you prove or disprove the hypothesis?
13. Applying Results What can you assume about the muscles that are needed
to move these bones?
14. Making Inferences What other factors may affect the characteristics of the
muscles required to move these bones?
15. Making Inferences How is the density of the different bones related to
how the organisms move? How is the density of the different bones related to
where the organism lives?
16. Applying Conclusions If an organism that was the size of a whale lived
on land, what kind of bones would the organism have? What kind of muscles
would the animal need to move those bones?
BIG IDEA QUESTION
17. Identifying Relationships Describe how the structure of a bone is related
to a life function of the animal. Make sure to include examples in your
answer.
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Skills Practice Lab
DATASHEET C
Structure and Function of Bone
The structure of each body part of an organism is related to the function of
that body part. For example, animals depend on specialized body parts for
movement. Animals contract and relax muscles that are attached to bones in
order to move. Some animals have legs, wings, or fins to move around. In
vertebrates, most movement is the result of bones and muscles working
together. Bones that support a lot of weight are thick and heavy, such as in
elephants. Bones that do not support a lot of weight are light, such as in the
wings of birds.
You have already learned that the bones of vertebrates have many
similarities. In this activity, you will compare the bone of a mammal, a bird,
and a fish. Through this activity, you will learn how differences in the
structure of different bones relate to the function of these bones.
OBJECTIVES
Determine the density of three kinds of animal bones.
Compare the bone of a mammal, a fish, and a bird.
Identify the relationship between the structure of the bone and the function of the
bone.
MATERIALS
 balance, laboratory
 beef bone
 chicken bone
 fish bone
 graduated cylinder, large
 string
 wire
SAFETY INFORMATION
Using Scientific Methods
ASK A QUESTION
1. Let’s ask, “Are the bones of animals that walk more dense than the bones of
animals that swim or of animals that fly?”
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Structure and Function of Bone continued
FORM A TESTABLE HYPOTHESIS
2. To change the question into a testable hypothesis, you should come up with
the following: “There are no differences in density between the bones of
animals that walk, swim, or fly.”
PROCEDURE
3. Create a table to record the mass (in g), volume (in cm3), and density (in
g/cm3) of the mammal, chicken, and fish bones.
4. Use a balance to determine the mass of a mammal bone. Record this value in
your table.
5. Fill a graduated cylinder about 3/4 full with water. Note the water level in the
cylinder. (Note: 1 mL = 1 cm3)
6. Tie a string around the beef bone. Gently lower it into the cylinder. When the
bone is completely submerged, note the new water level.
7. Determine the volume of the bone. Record your finding in your table.
8. Density is the mass of an object divided by the volume of the object.
Calculate the density of this bone. Record this value in your table.
9. Repeat steps 4–8 using a chicken bone and a fish bone. If a bone floats, you
will need to hold it under the surface of the water by using a length of wire.
ANALYZE THE RESULTS
10. Analyzing Results Did the bones sink or float?
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Structure and Function of Bone continued
11. Evaluating Results Which bone was the most dense? Which bone was the
least dense?
DRAW CONCLUSIONS
12. Drawing Conclusions Did you prove or disprove the hypothesis?
13. Applying Results Describe the relationship between the density of bones
and the muscles needed to move them.
14. Making Inferences What other factors may affect the characteristics of the
muscles required to move these bones?
15. Making Inferences How is the density of the different bones related to
how the organisms move and where the organism lives?
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Structure and Function of Bone continued
16. Applying Conclusions Imagine that an organism like a whale lived on
land. Describe the kind of bones and muscles it would need to have.
BIG IDEA QUESTION
17. Identifying Relationships Describe how the structure of a bone is related
to a life function of the animal. Make sure to include examples in your
answer.
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Science Skills Activity
DATASHEET
Constructing Distribution Maps
Teacher Notes
This activity walks students through how to create a map of the distribution of a
species of organisms (covers standard 7.7.d). Students may find it easier to
perform this activity if a large sheet of graph paper or a piece of poster board is
available for them to draw the map on. Have students include the table describing
the distribution of the Red beetle on their poster board. This will help them
visually relate the table to the distribution map that they have drawn.
MATERIALS
• paper, white
• pencils, colored
• ruler
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Science Skills Activity
DATASHEET
Constructing Distribution Maps
INVESTIGATION AND EXPERIMENTATION
7.7.d Construct scale models, maps, and appropriately labeled diagrams
to communicate scientific knowledge (e.g., motion of Earth’s plates and
cell structure).
TUTORIAL
Procedure
Use the following instructions to construct the distribution
map of a specific population of organisms.
Table 1
Distribution of Mountain Goats
Intersection
Population Size
1B
1
2B
20
2C
2
2D
25
3B
1
3C
30
3D
3
4D
40
5C
1
5D
1
Organizing A labelled grid has been placed on top of a map. Use
Table 1 to write the number of goats that were found at each
intersection.
Analysis
1. Evaluating Draw a line around the intersections that have at least one goat.
2. Evaluating In another color, draw a second line around the intersections that
have at least 10 goats.
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Constructing Distribution Maps continued
YOU TRY IT!
Procedure
Use the map and the data table below to construct a distribution map
of a population of rare red beetles.
Table 2
Distribution of Red Beetles
Intersection
Population Size
2A
1
2B
30
3B
5
3D
20
3E
3
4B
40
4C
30
4D
4
1.
Organizing Redraw the map shown here. Use Table 2 to write the number
of beetles that are found at each intersection.
Analysis
2. Evaluating Draw a line around the intersections that have at least one beetle.
In another color, draw a second line around the intersections that have at least
10 beetles.
3. Inferring Use the map to identify where the beetle is found. How might this
information be helpful if the beetle were becoming extinct?
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Answer Key
Directed Reading A
27.
28.
29.
30.
31.
32.
33.
34.
35.
36.
SECTION: WHAT IS AN ANIMAL?
1.
2.
3.
4.
5.
6.
7.
8.
9.
10.
11.
12.
13.
14.
15.
16.
17.
18.
19.
C
C
D
A
B
D
B
C
A
C
C
A
C
D
B
A
C
B
C
SECTION: INVERTEBRATES
1.
2.
3.
4.
5.
6.
7.
8.
9.
10.
11.
12.
13.
14.
15.
16.
17.
18.
19.
20.
21.
22.
23.
24.
SECTION: THE ANIMAL KINGDOM
1.
2.
3.
4.
5.
6.
7.
8.
9.
10.
11.
12.
13.
14.
15.
16.
17.
18.
19.
20.
21.
22.
23.
24.
25.
26.
B
A
A
C
C
B
A
C
B
A
A
D
C
B
D
C
B
C
B
A
D
B
B
D
A
B
B
B
A
D
C
B
C
A
B
C
C
A
B
C
D
C
B
C
A
C
A
B
B
A
C
C
B
A
A
B
A
B
C
A
SECTION: VERTEBRATES
1.
2.
3.
4.
5.
6.
7.
8.
9.
10.
11.
12.
D
A
A
D
B
C
C
D
A
B
C
A
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13.
14.
15.
16.
17.
18.
19.
20.
21.
22.
23.
24.
25.
26.
27.
28.
29.
30.
B
C
B
D
B
A
D
B
A
C
D
B
D
A
C
B
B
B
5.
6.
7.
8.
9.
10.
11.
12.
13.
14.
15.
16.
17.
18.
19.
20.
Directed Reading B
SECTION: WHAT IS AN ANIMAL?
21.
1.
2.
3.
4.
5.
6.
7.
8.
9.
10.
11.
12.
13.
14.
15.
16.
17.
18.
19.
C
D
C
D
A
C
C
B
A
A
B
C
A
D
B
B
B
C
Answers may vary. Sample answer: to search
for food, shelter, or mates
20. Muscle cells make most movement in animals
possible. Groups of these cells achieve
movement by contracting and relaxing.
21. by using energy released by chemical
reactions
22.
23.
24.
25.
26.
27.
28.
29.
30.
31.
32.
33.
34.
35.
36.
37.
38.
SECTION: INVERTEBRATES
1.
2.
3.
4.
5.
SECTION: THE ANIMAL KINGDOM
1.
2.
3.
4.
B
D
A
B
A
D
A
to make it easier to study all the different
kinds of animals
hydrozoans, jellyfish, and sea anemones and
corals
medusa, polyp
The young have the medusa form and can
move; the adults are polyps and can’t move.
an organism that invades and feeds on the
body of another organism
sexually, fragmentation
B
A
defense against predators; prevents the animal
from drying out
to help the animal move, eat, breathe, and
sense the environment
Males release sperm into the water, and
females release eggs into the water, where
they are fertilized by the males’ sperm.
C
B
A
B
C
A
C
D
A
A lancelet has a notochord but does not
develop a backbone.
B
A
All mammals have hair; females produce milk
for their young.
C
A
B
A
B
B
D
C
D
B
B
A
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6.
7.
8.
9.
10.
11.
12.
13.
14.
15.
16.
17.
18.
19.
20.
21.
B
D
A
A
B
A
Answers may vary. Sample answer: Insects
have different types of wings; some
invertebrates have legs to help them burrow;
other invertebrates have strong bodies for
swimming.
asymmetrical
bilateral
radial
exoskeletons
respiration
excretory
mouth, anus, stomach, intestine
egg, larva, pupa, adult
egg, nymph, adult
27. The circulatory system carries oxygen
collected by the respiratory system through the
body, and it returns carbon dioxide to the
respiratory system to expel it from the body.
28. Answers may vary. Sample answer: Animals
with larger brains depend more on learning
than on instinct.
Vocabulary and Section
Summary A
SECTION: WHAT IS AN ANIMAL?
1. coelom: a body cavity that contains the
internal organs
2. consumer: an organism that eats other
organisms or organic matter
3. differentiation: the process in which the
structure and function of the parts of an
organism change to enable specialization of
those parts
SECTION: THE ANIMAL KINGDOM
SECTION: VERTEBRATES
1.
2.
3.
4.
5.
6.
7.
8.
9.
10.
11.
12.
13.
14.
15.
16.
17.
18.
19.
20.
21.
22.
23.
24.
25.
26.
1. invertebrate: an animal that does not have a
backbone
2. exoskeleton: a hard, external, supporting
structure
3. vertebrate: an animal that has a backbone
4. endoskeleton: an internal skeleton made of
bone and cartilage
D
A
A
C
B
A
C
C
B
D
B
A
C
A
C
B
B
D
A
C
C
B
B
It is replaced by harder bone.
It aids in respiration.
In fish, water flows into the mouth and over
the gills, oxygen from the water moves over
the gills and into the bloodstream, and carbon
dioxide moves over the gills and back into the
water.
SECTION: INVERTEBRATES
1. segment: any part of a larger structure, such as
the body of an organism, that is set off by
natural or arbitrary boundaries
2. open circulatory system: a circulatory system
in which the circulatory fluid is not contained
entirely within vessels
3. closed circulatory system: a circulatory system
in which the heart circulates blood through a
network of vessels that form a closed loop
4. metamorphosis: a process in the lifecycle of
many animals during which a rapid change
from the immature organism to the adult takes
place
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SECTION: VERTEBRATES
SECTION: INVERTEBRATES
1. cartilage: a flexible and strong connective
tissue
2. small intestine: the organ between the stomach
and the large intestine where most of the
breakdown of food happens and most of the
nutrients from food are absorbed
3. large intestine: the wider and shorter portion
of the intestine that removes water from
mostly digested food and that turns the waste
into semisolid feces, or stool
1.
2.
3.
4.
5.
6.
7.
8.
SECTION: VERTEBRATES
1.
2.
3.
4.
5.
6.
7.
8.
9.
10.
11.
12.
Vocabulary and Section
Summary B
SECTION: WHAT IS AN ANIMAL?
Across
1. ectotherms
8. endotherms
9. fragmentation
11. coelum
Down
2. sexual reproduction
3. organ system
4. multicellular
5. consumer
6. differentiation
7. embryo
10. budding
invertebrate
exoskeleton
vertebrate
endoskeleton
pores
medusa
cartilage
sensory nerves
large intestine
motor nerves
small intestine
veins
anterior
dorsal
arteries
posterior
ventral
animals adapt
Reinforcement
WHO AM I?
1.
2.
3.
4.
5.
6.
SECTION: THE ANIMAL KINGDOM
1.
2.
3.
4.
5.
6.
segment
open circulatory system
closed circulatory system
metamorphosis
trachea
sense organs
brain
molting
7.
8.
9.
10.
11.
mantle
echinoderm
notochord
vertebrae
placenta
butterfly
sponge
snail
beetle
hydra
grasshopper
Critical Thinking
1. Answers may vary. Sample answer: This
sponge does not filter food particles from the
water. Instead, it uses hook-shaped filaments
to capture small organisms as they swim by.
2. Answers may vary. Sample answer: The cave
sponge would have trouble filter feeding
because of the lack of nutrients in the water. It
captures prey so that it doesn’t have to rely on
nutrients floating in the water.
3. Answers may vary. Sample answer: The cave
is cool, has few nutrients, and receives no
direct sunlight. All these conditions are similar
to those that might exist far below the sea
surface.
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4. Answers may vary. Sample answer: The sponge
adapted to the cave environment by developing a
new method of feeding. This is amazing because
sponges usually do not eat other animals.
5.
SciLinks Activity
1. Answers may vary. Sample answers:
Invertebrate
Drawing should
Name: butterfly
represent an
Body Plan: bilateral
invertebrate animal. symmetry
Reproduction: sexual
Habitat: all over the world
Interesting Fact: Butterfly
wings are made up of
many scales stacked like
shingles on a roof.
Drawing should
represent a
vertebrate animal.
6.
7.
8.
Vertebrate
Name: manatee
Body Plan: bilateral
symmetry
Reproduction: sexual
Habitat: tropical waters
Interesting Fact: The
manatee’s front teeth are
replaced by the back teeth
in a continual progression.
results in offspring that are genetically identical
to the parent. In sexual reproduction, offspring
are formed when the genetic information of two
parents combine.
Fish, snails, and algae are alive. The fish and the
snails are animals. Algae are not classified as
animals because they cannot move around on
their own and can perform photosynthesis.
A parrot could not fly if it did not have muscle
cells because muscles are made up of muscle
cells; muscles are required to contract and relax
to move the wing and support flight.
The body temperature of organism A increases as
the ground temperature increases. The body
temperature of organism B stays the same
regardless of the ground temperature.
Organism A is probably an ectotherm because its
body temperature changes with its environment.
Organism B is probably an endotherm because it
is able to maintain a steady body temperature
regardless of the ground temperature.
SECTION: THE ANIMAL KINGDOM
1. Sample answer: An exoskeleton is a hard,
supportive outer covering of an invertebrate.
2. Sample answer: All animals that have placentas
are known as vertebrates because they each have
a backbone unlike an invertebrate, which does
not have a backbone.
3. Cnidarians have two kinds of radially
symmetrical body plans, the medusa form and
the polyp form. The medusa is a cup or bellshaped body with tentacles that extend into the
water. The polyp is attached to a hard surface at
the base of the cup so that its tentacles extend
upwards and into the water. Cnidocytes are
specialized stinging cells in the tentacles that are
used to stun and capture prey.
4. Sample answer: Mollusks have a specialized
tissue called a mantle that secretes the shell of a
mollusk. Some mollusks also have a muscular
foot with which they are able to move.
Section Review
SECTION: WHAT IS AN ANIMAL?
1. Sample answer: An organism is called an embryo
during the early stages of its development. A
consumer is an organism that obtains energy and
nutrients from other organisms.
2. Sample answer: Differentiation is the process by
which cells specialize and develop the structures
needed to perform specific functions.
3. Cells that perform the same function and work
together form tissues. Different kinds of tissues
work together to perform specific functions in an
organ. Organs work together to perform specific
functions in an organ system. Organ systems
perform important functions for the life of the
organism.
4. The two main kinds of reproduction are asexual
reproduction and sexual reproduction. Asexual
reproduction requires only a single individual
and
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5. Sample answer: Two main differences
between sponges and roundworms are that
sponges are asymmetrical and do not have a
coelom, while roundworms are bilaterally
symmetrical and do have a coelom.
6. All chordates, including vertebrates, have a
notochord but only vertebrates have a
backbone.
7. I would classify a female organism that is
covered in fur and provides milk for its young
as a mammal.
8. Adult amphibians have to live near water or in
a very wet habitat because their eggs and
larvae need water or a very wet habitat. Adult
amphibians also need to keep their skin moist.
9. The organism in (a) has an exoskeleton. The
organism in (b) has an endoskeleton.
10. yes; I could classify these organisms as
vertebrates or invertebrates based on the kind
of skeleton they have because I can see
whether or not they have a backbone.
11. 21.4 g/day; 15 g × 10 = 150 g in a week; 150 g
 7 days in a week = 21.4 g/day
12. Reptiles can live nearly anywhere on land
because they do not have to lay their eggs in
water or in a very moist place. Reptile eggs
have special characteristics that prevent them
from drying out on land.
4. Two main differences between nymphs and
adults in the life cycle of a grasshopper are
that nymphs do not have wings like adults do
and nymphs are smaller than adults are.
5. I would expect an animal that had a head to
have bilateral body symmetry.
6. Butterflies undergo complete metamorphosis,
which has four stages: egg, larva, pupa, and
adult. Butterfly larvae and butterfly pupae
look very different from adult butterflies.
Grasshoppers undergo incomplete
metamorphosis, which has three stages: egg,
nymph, and adult. Grasshopper nymphs look
like smaller adults.
7. In an open circulatory system, the blood
moves through open spaces in the body. In a
closed circulatory system, blood moves
through tubes that form a closed loop.
8. Earthworms are in a different group than
roundworms because earthworms are
segmented, while roundworms are not
segmented.
9. Insects cannot see in complete darkness
because there is no light entering their eyes.
10. 93.3%; 178 – 12 = 166; 166/178 × 100 =
93.3%
11. no; The insect would not drown because it
takes in oxygen through the holes in the sides
of its body and not through its head.
12. Invertebrates that have noses and ears must
also have a head.
SECTION: INVERTEBRATES
1. Respiration is important because all animals
must perform respiration to live. Respiration is
the process in which oxygen is taken into the
body and carbon dioxide is released from the
body. In insects, oxygen moves through holes
in the sides of insects’ bodies into a network
of tubes called tracheae.
2. The body of a sponge is supported by jellylike material and tiny, glassy structures,
whereas the body of an insect is supported by
a tough exoskeleton.
3. Insects remove the wastes produced by their
cells through their excretory systems.
SECTION: VERTEBRATES
1. Different kinds of cells develop in an embryo
through the process of differentiation.
2. The backbone is made up of many vertebrae
that surround and protect the spinal cord. The
backbone also supports the body.
3. Vertebrates have closed circulatory systems.
4. There are 71 species of fish that are
endangered in the United States.
5. There are 133 species of fish that are
threatened or endangered in the United States.
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6. Gas exchange in the gills differs from gas
exchange in the lungs because the oxygen is
removed directly from the water by the gills
whereas oxygen is removed from the air in the
lungs.
7. An advantage of depositing a large number of
eggs is that a larger percentage of the offspring
may survive. A disadvantage of depositing a
large number of eggs is that the parent cannot
provide much parental care for so many
offspring, which would further increase the
chances of survival of the offspring.
8. An egg becomes fertilized when the nucleus of
a sperm cell fuses with the nucleus of an egg
cell. This is sexual reproduction because it
requires two sex cells from two different
parents.
9. Sample answer: Gravity and the ability to
maintain a large skeleton are two of the factors
that might limit the maximum body size that
land vertebrates can grow to.
10. Larger ears may be better able to hear a sound
than smaller ears can because larger ears are
able to capture more sound waves than smaller
ears can.
10.
11.
12.
Chapter Review
13.
14.
1. differentiation
2. An endoskeleton provides support from the
inside of the body. An exoskeleton provides
support from the outside of the body.
3. An invertebrate is an animal that does not have
a backbone. A vertebrate is an animal that
does have a backbone.
4. In asexual reproduction, a single parent
produces a genetically identical offspring. In
sexual reproduction, the sex cells from two
parents fuse to develop into an offspring.
5. B
6. D
7. A
8. B
9. The seven basic characteristics that most
animals have are as follows: All animals are
made up of cells; most animals have levels of
structural organization in their bodies; animal
15.
16.
17.
18.
19.
bodies either have one of two kinds of
symmetry or no symmetry at all; animals
consume other organisms to get the energy
that they need to live; animals reproduce and
develop; most animals are able to move
around; animals need to maintain the
temperature of their body within a specific
range of temperatures.
Insects that develop into adults from nymphs
undergo incomplete metamorphosis because
the nymphs are already very similar in
structure to adults.
Fragmentation in sponges is a form of asexual
reproduction because it only requires one
parent, whereas reptiles reproduce sexually,
which requires two parents.
Sample answer: The simplest level of
structural organization in a shark is a cell. A
group of similar cells that work together and
perform a similar function forms a tissue. A
group of tissues working together to perform a
specific function forms an organ. A group of
organs working together to perform a life
function forms an organ system. Many organ
systems work together to keep the shark alive.
a is the head; b is the thorax; c is the abdomen
The legs of the animal are attached to the
thorax.
I would classify this animal as an arthropod
because it is an insect and it has an
exoskeleton.
Sample answer: Many muscles are attached to
bones. As these muscles contract and relax,
the muscles move the bones, allowing the
animal to move around.
An answer to this exercise can be found at the
end of the Teacher Edition.
Vertebrates are classified as chordates because
vertebrates have a notochord at some point in
their development.
Three groups of mammals are monotremes,
which lay eggs; marsupials, which have a
pouch in which embryos develop; and
placental mammals, which have a placenta in
their uterus.
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20. If differentiation in an embryo is stopped, the
embryo will die because the cells will be
unable to specialize and perform the specific
life functions.
21. no; I could not learn about the life cycle of an
animal by studying only the adult forms of the
animal. The animal might have very different
body forms in the other stages of its life cycle.
22. When light enters a dog’s eyes, signals are
sent to the dog’s brain. The brain interprets the
signals as an image. The brain then sends
signals to the body of the dog so that it can
fetch the ball.
23. Unlike the cat, the gecko will die because it
will not be able to maintain its body
temperature within the range of temperatures
that it needs to live.
24. The bird is more likely to provide parental
care for its young.
25. The fish has a closed circulatory system, while
the insect has an open circulatory system.
26. About two more salamander species are
threatened or endangered than are species of
frogs and toads together.
27. The percentage of toads in the pie graph will
decrease as endangered toad species become
extinct.
28. Twenty percent of each female’s offspring
would need to survive to replace each male
and female parent and keep the population size
constant.
29. On land, vertebrates are larger than
invertebrates are because the vertebrate
skeleton can support a larger body than the
invertebrate systems can support.
SECTION: THE ANIMAL KINGDOM
1.
2.
3.
4.
5.
6.
7.
8.
9.
SECTION: INVERTEBRATES
1.
2.
3.
4.
5.
6.
7.
8.
9.
10.
B
E
C
A
D
A
D
B
C
A
SECTION: VERTEBRATES
1.
2.
3.
4.
5.
6.
7.
8.
9.
10.
C
B
A
D
C
C
B
B
D
C
Chapter Test A
Section Quizzes
1.
2.
3.
4.
5.
6.
7.
8.
9.
10.
11.
12.
13.
14.
15.
16.
17.
SECTION: WHAT IS AN ANIMAL?
1.
2.
3.
4.
5.
6.
7.
8.
9.
10.
C
B
D
A
A
D
A
A
C
E
D
A
C
B
A
A
B
D
D
A
B
D
A
C
C
A
C
B
D
B
A
D
C
A
B
D
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18.
19.
20.
21.
22.
23.
24.
25.
26.
27.
28.
29.
A
B
C
B
A
C
complete metamorphosis
cartilage
segments
tracheae
coelom
consumer
6.
7.
8.
9.
10.
11.
12.
13.
14.
15.
Chapter Test B
1.
2.
3.
4.
5.
6.
7.
8.
9.
10.
11.
12.
13.
14.
15.
16.
17.
18.
19.
20.
21.
22.
23.
24.
25.
26.
27.
28.
29.
30.
31.
B
D
A
A
C
A
D
B
B
C
D
B
A
C
C
E
B
D
F
A
D
A
C
B
B
A
C
C
D
A
B
16.
17.
18.
19.
digestive system
coelom
D
C
B
A
C
A
The two main groups of animals are
vertebrates, which have a backbone, and
invertebrates, which do not have a backbone.
Answers may vary. Sample answer: In an open
circulatory system, blood moves through open
spaces in the body. Most mollusks have an
open circulatory system.
The main respiratory organ in a fish is its gills,
while the main respiratory organ in a mammal
is its lungs.
Answers may vary. Sample answer: A lancelet
is not considered a vertebrate because
although it has a notochord, its notochord does
not develop into a backbone.
Answers may vary. Sample answer: The
butterfly develops separately from its parent
through the process of complete
metamorphosis. In this process, the butterfly
rapidly changes from an egg that has resulted
from sexual reproduction. The butterfly then
passes through larva and pupa stages and on to
its adult form as a genetically unique
individual organism. The hydra, however,
develops through an asexual form of
reproduction called budding. In this process,
the offspring develops as a part of the parent
organism. The genetically identical offspring
then pinches off from the parent to live
independently.
Answers may vary. Sample answer: Both
endoskeletons and exoskeletons provide a
structure for organ support and serve as a
place for muscles to attach. Endoskeletons are
found in vertebrates, and exoskeletons are
found in invertebrates.
Chapter Test C
1.
2.
3.
4.
5.
differentiation
segments
consumer
closed circulatory system
sensory nerves
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20. Answers may vary. Sample answer: Frogs and
fish lay eggs. The male fertilizes the eggs after
the female deposits them in a safe area. This is
sexual reproduction because it involves the
joining of egg and sperm to produce offspring
with characteristics of both parents.
21. a. vertebrates; b. birds; c. sponges; d. feathers;
e. asymmetrical; f. flight
4. Answers may vary. Students should be able to
describe the general differences between the
two kinds of animals.
5. Answers may vary. Students should be able to
identify how the two kinds of animals move
and the structures that the animals use to
move.
6. Answers may vary. Students may not be able
to locate the “mouth” of an animal, such as a
worm. Encourage students who cannot
determine what an animal eats to conduct
research on the animal’s diet, eating habits,
and how it finds or catches food.
Performance-Based
Assessment
1. Answers may vary. Sample answer: The
temperature of the water in each can is 76°C.
2. Answers may vary. Sample answer: The
temperature of the water in the can surrounded
by feathers is 63°C. The temperature of the
water in the other can is 59°C.
3. Answers may vary. Sample answer: The can
under the pillow was warmer after 15 minutes.
The down feathers insulated the can.
4. Answers may vary. Sample answer: The
feathers are structured differently because the
down feather is structured to help the bird
maintain its body temperature, while the
contour feather is designed to maintain its
shape for flight or other functions.
5. Answers may vary. Sample answer: Down
feathers are fuzzy and airy, qualities that are
perfect for trapping body heat and keeping the
bird warm. The function of the rigid shaft is to
maintain the structure of the feather. The
function of the barbs on a contour feather is to
form a smooth, aerodynamic surface. Barbs
and barbules link together to give the feather
strength and shape.
DATASHEET B
3. Answers may vary, but should include
information on the appearance of each animal
and each animal’s activities.
4. Answers may vary, but should include
descriptions of the differences between the
two kinds of animals.
5. Answers may vary, but students should
identify how the animals move and the
structures that the animals use to move.
6. Answers may vary. Students may not be able
to locate the “mouth” of an animal such as a
worm. Encourage students who cannot
determine what an animal eats to conduct
research on the animal’s diet, eating habits,
and how it finds or catches food.
DATASHEET C
3. Answers may vary, but should include
information on the appearance of each animal
and each animal’s activities.
4. a. Answers may vary. Students should be able
to describe the general differences between the
two kinds of animals.
b. Answers may vary. Students should
describe characteristics of animals: they are
multicellular organisms; they have specialized
cells, tissues, organs, and organ systems; most
have bilateral or radial symmetry; they
consume other organisms for energy; they
reproduce asexually or sexually; they move;
they must maintain their body temperature.
Explore Activity
DATASHEET A
3. Answers may vary, but students may refer to
characteristics, such as how the animals
moved, what they were eating, and what type
of body they had.
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5. Answers may vary, but students should
identify how the animals move and the
structures that the animals use to move.
6. Answers may vary. Students may not be able
to locate the “mouth” of an animal, such as a
worm. Encourage students who cannot
determine what an animal eats to conduct
research on the animal’s diet, eating habits,
and how it finds or catches food.
DATASHEET B
Answers may vary depending on the list of
organisms the students choose to explore.
Students should be able to articulate their
reasons for their choices.
DATASHEET C
4. Answers may vary depending on the list of
organisms the students choose to explore.
Students should be able to articulate their
reasons for their choices.
5. Answers may vary depending on the list of
organisms the students choose to explore.
Students should be able to articulate their
reasons for their choices and why they think
the characteristics that the other student used
are logical.
Quick Lab: Differentiating
Blood Cells
DATASHEET A
2. Make sure that students’ sketches show that
red blood cells are round and concave while
white blood cells are larger and more irregular
in shape.
3. Point out differences between the stem cell
and the cells in the students’ sketches.
Quick Lab: Seeing Like an
Insect
DATASHEET B
DATASHEET A
2. Sketches should show round, concave red
blood cells; large, irregularly-shaped white
blood cells.
3. Point out the differences between the stem cell
and the cells in the students’ sketches.
5. Answers may vary according to the picture
provided.
6. squares of the grid
7. The images the insect sees would also be more
curved.
DATASHEET C
DATASHEET B
2. Sketches should show that red blood cells are
round and concave while white blood cells are
larger and more irregular in shape. Students
should describe how the cells differ in size and
shape.
3. Answers may vary, but students should be able
to describe the differences between the blood
stem cell and the red and white blood cells.
5. Answers may vary according to the picture
provided.
6. The squares of the grid mimicked the
repeating units in the eye of an insect.
7. The images would also be more curved.
DATASHEET C
5. Answers may vary according to the picture
provided.
6. The squares of the grid mimicked the
repeating units of the eye of an insect.
7. The images would also be more curved.
Quick Lab: Grouping
Organisms by Characteristics
DATASHEET A
Answers may vary depending on the list of
organisms the students choose to explore.
Students should be able to articulate their
reasons for their choices.
Quick Lab: Amplifying Sound
DATASHEET A
4. The sound should be loudest when the cone is
positioned directly towards the sound.
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5. The larger the cone, the more easily and
clearly a sound is heard.
16. If an animal as large as a whale lived on land,
it would have to have very large, dense bones
to which large muscles were attached to move
the bones. Large, dense bones would be
needed to support the weight of the body, and
the muscles would have to be strong enough to
move the bones.
17. Accept all reasonable answers. Students
should be able to articulate the reasons for
their examples based on considerations, such
as the weight being supported and the type of
movement required.
DATASHEET B
4. The sound should be loudest when the cone is
positioned directly towards the sound.
5. The larger the cone, the more easily and
clearly a sound is heard.
DATASHEET C
4. The sound should be loudest when the cone is
positioned directly towards the sound.
5. The larger the cone, the more easily and
clearly a sound is heard.
DATASHEET B
Chapter Lab
10. Answers may vary. The chicken bone and the
beef bone are most likely to sink. Although
fish bones are the least dense, some fish bones
may also sink.
11. The beef bone is the most dense. The fish bone
is the least dense.
12. Sample answer: My original hypothesis was
disproved.
13. Larger muscles are needed to move the denser
and heavier bones.
14. The size and shape of the muscles would be
different relative to the bone and according to
how the muscle is involved in movement. For
example, larger muscles are required for an
animal to fly than for an animal with similarsized bones to walk.
15. The mammal bone is more dense than the bird
bone or fish bone because the bone of a
mammal, such as a cow, must support a
greater weight than that of a bird or of a fish.
The bone of a bird is less dense than the bone
of a mammal because it needs to be both
strong and light enough for the bird to fly. Fish
bones are the least dense because fish bones
do not have to support the weight of the fish’s
body in the same way that the bones of land
animals do. The bones of a fish must be light
and flexible so that the fish can swim without
sinking.
DATASHEET A
10. Answers may vary. The chicken bones and the
beef bones are most likely to sink. Although
fish bones are the least dense, some fish bones
may also sink.
11. The beef bone is the most dense. The fish bone
is the least dense.
12. Sample answer: Yes. My original hypothesis
was disproved.
13. Yes. Larger muscles are needed to move the
denser and heavier bones.
14. Yes. The size and shape of the muscles would
be different relative to the bone and according
to how the muscle is involved in movement.
For example, larger muscles are required for
an animal to fly than for an animal with
similar-sized bones to walk.
15. Sample answer: The mammal bone is more
dense than the bird bone or fish bone because
the bone of a mammal, such as a cow, must
support the weight of the mammal. The bone
of a bird is less dense than the bone of a
mammal so that it is light and strong enough
for the bird to fly. Fish bones are the least
dense because fish bones do not have to
support the weight of the body in the same
way as in mammals. This is because fish live
in water. The bones of a fish must be light and
flexible so that the fish can swim without
sinking in the water.
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16. If an animal as large as a whale lived on land,
it would have to have very large, dense bones
and large muscles attached to the bones to
move the bones. Large, dense bones would be
needed to support the weight of the body and
the muscles would have to be strong enough to
move the bones.
17. Accept all reasonable answers. Students
should be able to articulate the reasons for
their examples based on considerations, such
as the weight being supported and the type of
movement required.
16. If an animal as large as a whale lived on land,
it would have to have very large, dense bones
to which large muscles were attached to move
the bones. Large, dense bones would be
needed to support the weight of the body, and
the muscles would have to be strong enough to
move the bones.
17. Accept all reasonable answers. Students
should be able to articulate the reasons for
their examples based on considerations, such
as the weight being supported and the type of
movement required.
DATASHEET C
Science Skills Activity
10. Answers may vary. The chicken bones and the
beef bones are most likely to sink. Although
fish bones are the least dense, some fish bones
may also sink.
11. The beef bone is the most dense. The fish bone
is the least dense.
12. Sample answer: My original hypothesis was
disproved.
13. Larger muscles are needed to move the denser
and heavier bones.
14. Sample answer: The size and shape of the
muscles would be different relative to the bone
and according to how the muscle is involved
in movement. For example, larger muscles are
required for an animal to fly than for an
animal with similar-sized bones to walk.
15. Sample answer: The mammal bone is more
dense than the bird bone or fish bone because
the bone of a mammal, such as a cow, must
support a greater weight than that of a bird or
of a fish. The bone of a bird is less dense than
the bone of a mammal because it needs to be
both strong and light enough for the bird to
fly. Fish bones are the least dense because fish
bones do not have to support the weight of the
fish’s body in the same way that the bones of a
land animal do. The bones of a fish must be
light and flexible so that the fish can swim
without sinking.
DATASHEET
2. Students’ distribution map should resemble
the following:
3. The highest numbers of Red beetles are found
along the edge of the river. This information
would be useful if this beetle were becoming
extinct because steps could be taken to protect
the areas along the edge of the river. This
would help maintain these areas for the Red
beetle.
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