Characteristics of Animals
Animals are multicellular, heterotrophic organisms with cells that lack cell walls.
Animals are often informally grouped as invertebrates or vertebrates, although
vertebrates make up only a subgroup of one phylum—Chordata. The vast
majority of animals are invertebrates.
Vertebrates are chordates with a backbone. They take their name from the
individual segments, called vertebrae that make up the backbone. In most
vertebrates, the backbone completely replaces the notochord found in
invertebrate chordates.
The backbone provides support for and protects a dorsal nerve cord. It also
provides a site for muscle attachment. These functions paved the way for the
development of an internal skeleton that allowed vertebrates to grow larger than
their invertebrate ancestors. In addition to a backbone, most vertebrates have a
bony skull that encases and protects their brain.
Vertebrates share a number of other characteristics, including segmentation,
bilateral symmetry, and two pairs of jointed appendages, such as limbs or fins.
They exhibit cephalization and have a complex brain and sense organs. All
vertebrates have a true coelom and a closed circulatory system with a
chambered heart.
Answer the following questions and tape them to the 1st question section of your VIQs pg
1. What is an animal?
2. What is a vertebrate?
3. To what phylum do all vertebrates belong?
4. What are the individual segments that make up the backbone called, and what is the
significance of their name?
5. How does this structure differ in invertebrate chordates?
6. What are three functions of the backbone?
7. The development of the backbone paved the way for what other significant development
that allowed vertebrates to grow larger than land invertebrates?
8. What structure encases and protects the brain of vertebrates?
9. List five other characteristics that vertebrates share.
An analogy is a comparison. In the space provided, write the letter of the term that best
completes the analogy.
_____ 10. Vertebrate is to backbone as invertebrate chordate is to
a. brain.
b. sense organs.
c. circulatory system.
d. notochord.
VIQs –
Ready the following passages and answer the questions pertaining to each
passage. Glue both passages to page 50 of your BIN.
Animal Body Systems
One of the keys to the success of animals is the animals’ ability to move. In
order to move, their bodies need support. An animal’s skeleton provides a
framework that supports the animal’s body. Soft-bodied animals have a
hydrostatic skeleton, which is a water-filled cavity under pressure. Other
invertebrates have an exoskeleton, which is a rigid external skeleton that
encases the body of an animal. Humans and other vertebrates have an
endoskeleton, which is internal and made of a hard material, such as bone.
The digestive system is responsible for extracting energy and nutrients from
an animal’s food, while the excretory system removes metabolic waste products
from the animal’s body.
The nervous system carries information about the environment through the
body and coordinates responses and behaviors.
The respiratory system is responsible for exchanging oxygen and carbon
dioxide between the body and the environment. The circulatory system
transports gases, nutrients, and other substances within the body.
Animal Reproduction
Reproduction that does not involve the fusion of two gametes is called
asexual reproduction. A sponge, for example, can reproduce by simply
fragmenting its body. Each fragment grows into a new sponge. An unusual
method of asexual reproduction is parthenogenesis, in which a new individual
develops from an unfertilized egg.
In sexual reproduction, a new individual is formed by the union of a male
gamete and a female gamete. Gametes are produced in the sex organs. The
testes produce the male gametes (sperm), and the ovaries produce the female
gametes (eggs). Some species of animals, called hermaphrodites, have both
testes and ovaries. Many simple invertebrates, including slugs, earthworms, and
some fishes, are hermaphrodites.
Answer the following questions. Glue the Animal Body Systems vocabulary matching into the Vocab
section of your VIQs on page 51 of your BIN Glue the Animal Reproduction questions to the first
questions section of your VIQs on page 51 of your BIN
Animal Body Systems ______
1. hydrostatic skeleton
a. external skeletal support
______
2. exoskeleton
b. transports nutrients among other things
______
3. endoskeleton
c. internal skeletal support
______
4. digestive system
d. a water-filled cavity under pressure
______
5. circulatory system
e. extracts nutrients among other things
In the space provided, write A if the description is true of asexual reproduction, S if the description is true
of sexual reproduction, or B if the description is true of both forms of reproduction.
____ 6.necessary for a species to survive
______
9. occurs in animals
____ 7.dependent on the actions of the testes & ovaries
______ 10. unites male and female gametes
____ 8.a sponge does this by body fragmentation
______ 11. one form is parthenogenesis
______ 12. Complete the analogy. Sperm is to testes as eggs are to
a. ovaries.
c. hermaphrodites.
b. parthenogenesis.
d. external fertilization
Answer the following questions. Glue the Animal Body Systems vocabulary matching into the Vocab
section of your VIQs on page 51 of your BIN. Glue the Animal Reproduction questions to the first
questions section of your VIQs on page 51 of your BIN
Animal Body Systems ______
1. hydrostatic skeleton
a. external skeletal support
______
2. exoskeleton
b. transports nutrients among other things
______
3. endoskeleton
c. internal skeletal support
______
4. digestive system
d. a water-filled cavity under pressure
______
5. circulatory system
e. extracts nutrients among other things
In the space provided, write A if the description is true of asexual reproduction, S if the description is true
of sexual reproduction, or B if the description is true of both forms of reproduction.
____ 6.necessary for a species to survive
______
9. occurs in animals
____ 7.dependent on the actions of the testes & ovaries
______ 10. unites male and female gametes
____ 8.a sponge does this by body fragmentation
______ 11. one form is parthenogenesis
______ 12. Complete the analogy. Sperm is to testes as eggs are to
a. ovaries.
c. hermaphrodites.
b. parthenogenesis.
d. external fertilization