Chapter 12 What Is a Vertebrate?
Table of Contents
Chapter
Preview
12.1 Structure
and Function of Vertebrates
12.1
12.2 What
FishesIs a Vertebrate?
12.2 Fishes
12.3 Amphibians
12.3 Amphibians
12.4 Reptiles
12.4 Reptiles
12.5 Birds
12.5 Birds
12.6 Mammals
12.6 Mammals
Chapter 12 What Is a Vertebrate?
Chapter Preview Questions
1. A group of similar cells that perform a specific function is
called a(n)
a. organ.
b. tissue.
c. organ system.
d. organism.
Chapter 12 What Is a Vertebrate?
Chapter Preview Questions
1. A group of similar cells that perform a specific function is
called a(n)
a. organ.
b. tissue.
c. organ system.
d. organism.
Chapter 12 What Is a Vertebrate?
Chapter Preview Questions
2. The major cause of extinction of species is
a. a change in the environment.
b. new diseases.
c. over-killing by predators.
d. competition with other species.
Chapter 12 What Is a Vertebrate?
Chapter Preview Questions
2. The major cause of extinction of species is
a. a change in the environment.
b. new diseases.
c. over-killing by predators.
d. competition with other species.
Chapter 12 What Is a Vertebrate?
Chapter Preview Questions
3. The term for the extinction of many organisms at the same
time is
a. Permian extinction.
b. Pangaea.
c. Cambrian explosion.
d. mass extinction.
Chapter 12 What Is a Vertebrate?
Chapter Preview Questions
3. The term for the extinction of many organisms at the same
time is
a. Permian extinction.
b. Pangaea.
c. Cambrian explosion.
d. mass extinction.
Chapter 12 What Is a Vertebrate?
Chapter Preview Questions
4. Most animals reproduce
a. sexually only.
b. asexually only.
c. with alternating sexual and asexual stages.
d. by binary fission.
Chapter 12 What Is a Vertebrate?
Chapter Preview Questions
4. Most animals reproduce
a. sexually only.
b. asexually only.
c. with alternating sexual and asexual stages.
d. by binary fission.
Chapter 12 What Is a Vertebrate?
How does the structure of vertebrates help them
to function?
Two friends are looking at fishes in an
aquarium. One friend refers to the fishes
as animals. The other friend argues that
fishes aren’t animals because they don’t
have four legs. Which friend is correct?
Explain your answer.
Chapter 12 What Is a Vertebrate?
Greek Word Origins
Greek Word
amphibios
Meaning of Greek Word
Key Term
living a double life
amphibian An animal that
spends part of its life cycle
on land and part in water
Chapter 12 What Is a Vertebrate?
Greek Word Origins
Greek Word
chordé
Meaning of Greek Word
Key Term
string, cord
chordate An animal that
has a flexible rod that
supports the animalís back
Chapter 12 What Is a Vertebrate?
Greek Word Origins
Greek Word
therme
Meaning of Greek Word
heat
Key Term
endotherm An animal that
produces enough heat
within its body to control its
body temperature
Chapter 12 What Is a Vertebrate?
Apply It!
1. How does the meaning of amphibian relate to the Greek word from
which it comes?
An animal that lives for part of its life on land and part in water is living
a double life.
2. Can you think of an English word besides chordate that might
come from the Greek word chordé?
Sample: cord
3. In the list of key terms on the next page, find another term
besides endotherm that might come from the Greek word
therme. Then look up the meaning of the key term and check
how its meaning relates to the meaning of endotherm.
An ectotherm is an animal whose body does not produce much internal
heat. An endotherm, in contrast, is an animal whose body does produce
internal heat to maintain its temperature.
Chapter 12 What Is a Vertebrate?
End of Chapter
Preview
Chapter 12 What Is a Vertebrate?
Section 1:
What Is a Vertebrate?
What are the characteristics of chordates and vertebrates?
How have scientists been able to infer the relationships of
major groups of vertebrates?
How do vertebrates differ in the way they control body
temperature?
Chapter 12 What Is a Vertebrate?
Ancient Jawless Fish
Look backward in time, into
an ocean 530 million years
ago. There you see a
strange-looking creature—a
jawless fish—that is about
as long as your index finger.
Chapter 12 What Is a Vertebrate?
Characteristics of Chordates
This lancelet shows the characteristics of a chordate: a
notochord, a nerve cord down its back, and gill slits.
Chapter 12 What Is a Vertebrate?
Evolution of Vertebrates
The pattern of vertebrate evolution is branching.
Chapter 12 What Is a Vertebrate?
Links on Vertebrates
Click the SciLinks button for links on vertebrates.
Chapter 12 What Is a Vertebrate?
Vertebrates
Click the Video button to watch a movie about vertebrates.
Chapter 12 What Is a Vertebrate?
End of Section:
What Is a Vertebrate?
Chapter 12 What Is a Vertebrate?
Section 2: Fishes
What are the characteristics of chordates and vertebrates?
How have scientists been able to infer the relationships of
major groups of vertebrates?
How do vertebrates differ in the way they control body
temperature?
Chapter 12 What Is a Vertebrate?
Characteristics of Fishes
Most fishes obtain oxygen
through gills. Water flows into
the mouth of the fish and then
over its gills. Oxygen moves
into the blood and is delivered
to the cells of the fish.
Chapter 12 What Is a Vertebrate?
Bony Fishes
A bony fish has jaws, scales, a pocket on each side of the
head that holds the gills, and a skeleton made of hard bones.
Chapter 12 What Is a Vertebrate?
End of Section: Fishes
Chapter 12 What Is a Vertebrate?
Section 3: Amphibians
What is the life cycle of an amphibian?
How are adult amphibians adapted to living on land?
Chapter 12 What Is a Vertebrate?
What Is an Amphibian?
During its metamorphosis from tadpole to adult, a frog’s body
changes dramatically.
Chapter 12 What Is a Vertebrate?
Living on Land
Many adult amphibians have lungs, a
heart with three chambers, and a
double-loop circulatory system.
Chapter 12 What Is a Vertebrate?
Respiration and Circulation Activity
Click the Active Art button to open a browser window and
access Active Art about respiration and circulation.
Chapter 12 What Is a Vertebrate?
More on The Frog Life Cycle
Click the PHSchool.com button for an activity about
the frog life cycle.
Chapter 12 What Is a Vertebrate?
End of Section:
Amphibians
Chapter 12 What Is a Vertebrate?
Section 4: Reptiles
What adaptations allow reptiles to live on land?
What are the characteristics of each of the three main
groups of reptiles?
What environmental change may have caused the
extinction of the dinosaurs?
Chapter 12 What Is a Vertebrate?
Adaptations for Life on Land
The membranes and shell of an amniotic egg protect the
developing embryo.
Chapter 12 What Is a Vertebrate?
The Sex Ratio of Newly Hatched Alligators
The temperature of the
developing eggs of the American
alligator affects the sex ratio of
the young. (Sex ratio is the
number of females compared
with the number of males.)
Chapter 12 What Is a Vertebrate?
The Sex Ratio of Newly Hatched Alligators
Reading Graphs:
At which temperature(s) did
only females hatch?
29.4ºC
Chapter 12 What Is a Vertebrate?
The Sex Ratio of Newly Hatched Alligators
Drawing Conclusions:
What effect does the
temperature of developing
eggs have on the sex of the
baby alligators?
The warmer the incubation
temperature, the greater the
proportion of males.
Chapter 12 What Is a Vertebrate?
The Sex Ratio of Newly Hatched Alligators
Calculating:
If 100 eggs developed at
31.7ºC, about how many of
the young would be male?
According to the graph, out of the
50 alligators that were incubated at
31.7ºC, about 40 (or 80%) were
males. So 80% of 100 eggs (80)
could be expected to hatch as
males.
Chapter 12 What Is a Vertebrate?
Extinct Reptiles–The Dinosaurs
Climate change may have caused the
extinction of dinosaurs and other
organisms.
Chapter 12 What Is a Vertebrate?
More on Reptiles
Click the PHSchool.com button for an activity about reptiles.
Chapter 12 What Is a Vertebrate?
Interpreting Fossils
Click the Video button to watch a movie about
interpreting fossils.
Chapter 12 What Is a Vertebrate?
End of Section:
Reptiles
Chapter 12 What Is a Vertebrate?
Section 5: Birds
What are the main characteristics of birds?
Chapter 12 What Is a Vertebrate?
Characteristics of Birds
The bodies of most birds have adaptations for flight.
Chapter 12 What Is a Vertebrate?
Characteristics of Birds
Air sacs and a four-chambered heart help birds obtain
oxygen and move it to their cells.
Chapter 12 What Is a Vertebrate?
Characteristics of Birds
Birds have four-chambered hearts and
double-loop circulatory systems that efficiently
move oxygen to their cells.
Chapter 12 What Is a Vertebrate?
Respiration and Circulation Activity
Click the Active Art button to open a browser window and
access Active Art about respiration and circulation.
Chapter 12 What Is a Vertebrate?
Characteristics of Birds
Some birds like this hawk have a crop and a gizzard. The
crop stores food, and the gizzard crushes food.
Chapter 12 What Is a Vertebrate?
End of Section: Birds
Chapter 12 What Is a Vertebrate?
Section 6: Mammals
What characteristics do all mammals share?
What are the main groups of mammals and how
do they differ in their reproduction?
Chapter 12 What Is a Vertebrate?
Diversity of Mammals
The three main groups of mammals are monotremes,
marsupials, and placental mammals.
kangaroo
spiny anteater
giraffe
Chapter 12 What Is a Vertebrate?
Mammal Diversity
This circle graph shows the
percentage of species of
some types of mammals.
Chapter 12 What Is a Vertebrate?
Mammal Diversity
Reading Graphs:
What percentage of species
are bats?
21.8 %
Chapter 12 What Is a Vertebrate?
Mammal Diversity
Calculating:
What percentage of species
are not bats?
78.2 %
Chapter 12 What Is a Vertebrate?
Mammal Diversity
Graphing:
Suppose you used the data
shown in the circle graph to
make a bar graph. Which bar
would be tallest?
The group with the greatest
number of species, rodents,
would be the tallest.
Chapter 12 What Is a Vertebrate?
Mammal Diversity
Predicting:
What total should all the
percentages in the pie chart
add up to? Do you have to
add the percentages to obtain
your answer? Explain
100; no, you do not have to add
them because it is a circle
chart—the entire chart stands for
100 percent of the items
counted— in this case, mammal
species.
Chapter 12 What Is a Vertebrate?
Links on Mammals
Click the SciLinks button for links on mammals.
Chapter 12 What Is a Vertebrate?
End of Section:
Mammals
Chapter 12 What Is a Vertebrate?
QuickTake Quiz
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