Name: 
 

CH. 13 Birds and Mammals



Modified True/False
Indicate whether the sentence or statement is true or false.  If false, change the identified word or phrase to make the sentence or statement true.
 

1. 

All birds have hearts with four chambers. _________________________

 

2. 

Birds have contour feathers that are specialized to trap heat. _________________________

 

3. 

The toes of perching birds can automatically lock onto a branch. _________________________

 

4. 

The shells of bird eggs are harder than the shells of reptile eggs. _________________________

 

5. 

During flight, the air above the wing exerts less pressure than the air beneath the wing. _________________________

 

6. 

During flight, air moves faster over the lower surface of each wing. _________________________

 

7. 

All mammals are endothermic vertebrates. _________________________

 

8. 

Sharply pointed teeth that stab food and tear into it are called incisors. _________________________

 

9. 

Marsupial mammals are at a(n) later stage of development at birth than placental mammals are at birth. _________________________

 

10. 

The gestation period of marsupials is longer than that of placental mammals. _________________________

 

Multiple Choice
Identify the letter of the choice that best completes the statement or answers the question.
 

11. 

Birds are the only animals that have
a.
scales.
b.
feathers.
c.
nests.
d.
a heart with four chambers.
 

12. 

Evidence indicates that birds are descended from
a.
reptiles.
b.
mammals.
c.
insects.
d.
segmented worms
 

13. 

A bird's nearly hollow bones help it to
a.
build a nest.
b.
deliver oxygen to its cells.
c.
fly.
d.
defend itself against predators.
 

14. 

Feathers keep a bird warm by
a.
giving the bird a streamlined shape.
b.
helping a bird sweat.
c.
trapping air next to the bird's body.
d.
raising the temperature of the environment.
 

15. 

Some birds swallow small stones, which help the birds
a.
fly faster.
b.
keep warm.
c.
stay flexible.
d.
digest food.
 

16. 

Where do many birds store food that they are not ready to digest?
a.
in the crop
b.
in the gizzard
c.
in the stomach
d.
in the air sacs
 

17. 

Which of these structures help birds get enough oxygen?
a.
air sacs
b.
feathers
c.
gizzards
d.
bones
 

18. 

The toes of perching birds are adapted to help the birds
a.
wade in water.
b.
lock onto a branch.
c.
walk across ice.
d.
crack seeds open.
 

19. 

What adaptation helps an ostrich survive in its environment?
a.
It uses its broad bill to catch underwater animals.
b.
It uses its strong legs to run away from predators.
c.
It uses its large feathers to keep itself warm.
d.
It uses its long neck to burrow into sand.
 

20. 

Birds play an important role in the environment by
a.
creating air currents with their wings.
b.
providing feathers for down jackets.
c.
carrying seeds to new locations.
d.
helping to eliminate air pollution.
 

21. 

As a bird's wing moves forward through the air, the air pressure on the wing
a.
goes away.
b.
pushes the wing downward.
c.
is greater above the wing than beneath it.
d.
is less above the wing than beneath it.
 

22. 

What is the name of the upward force that enables a bird to fly?
a.
lift
b.
gravity
c.
air pressure
d.
flight path
 

23. 

Which type of flight requires the bird to exert the most energy?
a.
gliding
b.
soaring
c.
diving
d.
flapping
 

24. 

During soaring flight, a bird
a.
rises on a current of warm air.
b.
coasts downward through the air.
c.
moves its wings rapidly.
d.
folds its wings against its body.
 

25. 

Which characteristic is common to all mammals?
a.
They are ectotherms.
b.
Their hearts have four chambers.
c.
Their skin is completely covered with hair or fur.
d.
Their young are born alive.
 

26. 

The earliest mammals were
a.
large animals that looked a lot like today's elephants.
b.
small, mouse-sized animals.
c.
flying mammals.
d.
mammals that did not feed their young with milk.
 

27. 

Mammals are probably descended from
a.
birds.
b.
arthropods.
c.
mollusks.
d.
reptiles.
 

28. 

Unlike most mammals, bats are able to
a.
fly.
b.
swim.
c.
walk.
d.
crawl.
 

29. 

Fur is an adaptation that allows mammals to
a.
care for their young.
b.
find prey.
c.
survive in cold climates.
d.
let their body heat escape.
 

30. 

A strand of hair or fur is composed of
a.
dead cells.
b.
living cells.
c.
scales.
d.
a rubberlike material.
 

31. 

The large muscle that enables mammals to breathe in and out is called the
a.
lung.
b.
respiratory muscle.
c.
cardiac muscle.
d.
diaphragm.
 

32. 

How many types of teeth are found in mammals?
a.
one
b.
two
c.
three
d.
four
 

33. 

Most mammals have four different types of teeth: incisors, canines, premolars, and molars.

What is the function of canine teeth in most mammals?
a.
to stab food and tear into it
b.
to bite off and cut parts of food
c.
to shred and grind food into small bits
d.
to scrape small pieces from the surface of food
 

34. 

What characteristic is used to classify a mammal species as a monotreme, marsupial, or placental mammal?
a.
the environment in which it lives
b.
how much hair or fur it has
c.
the structure of its brain
d.
the way in which its young develop
 

35. 

Which type of mammal lays eggs?
a.
marsupial
b.
monotreme
c.
placental mammal
d.
marine mammal
 

36. 

Which of these animals is a monotreme?
a.
duck-billed platypus
b.
kangaroo
c.
whale
d.
mouse
 

37. 

A mammal's gestation period is the length of time
a.
during which the mammal is dependent on its mother.
b.
between fertilization and birth.
c.
between egg-laying and hatching.
d.
for which it hibernates.
 

38. 

Where does a placental mammal develop before its body systems can function independently?
a.
inside its mother's body
b.
in a pouch on its mother's body
c.
in a nest near its mother's body
d.
inside an egg that is protected by the mother
 

39. 

The function of the placenta is to
a.
pass materials between the mother and an embryo.
b.
protect an embryo from heat and cold.
c.
keep an embryo inside its mother.
d.
prevent an embryo from drying out.
 

40. 

Which mammals have the longest gestation period?
a.
insect-eaters such as moles
b.
hoofed mammals such as zebras
c.
large mammals such as elephants
d.
gnawing mammals such as squirrels
 

Completion
Complete each sentence or statement.
 

41. 

Birds have ____________________ feathers that give shape to their bodies.
 

 

42. 

A bird's ____________________ churns and grinds food.
 

 

43. 

Birds have ____________________ that connect to the lungs and increase the amount of oxygen birds can take in.
 

 

44. 

After birds swallow food, they store it in their ____________________.
 

 

45. 

The structure of a duck's ____________________ enables the duck to filter food from water.
 

 

46. 

Birds help plants to ____________________ by carrying pollen and seeds from one place to another.
 

 

47. 

The speed at which an ostrich can ____________________ helps it escape from predators.
 

 

48. 

The two-loop circulatory system of a bird is efficient at delivering ____________________ to cells.
 

 

49. 

The type of flying that requires the most energy is called ____________________.
 

 

50. 

The difference in pressure above and below a bird's wing produces an upward force called ____________________.
 

 

51. 

The type of flight in which birds rise on currents of warm air is called ____________________.
 

 

52. 

During ____________________ flight, a bird coasts downward through the air.
 

 

53. 

A large muscle called the ____________________, which is located at the bottom of the chest, helps mammals to breathe.
 

 

54. 

The number of chambers in a mammal's heart is ____________________.
 

 

55. 

Mammary glands are organs that produce ____________________.
 

 

56. 

Mammals have an insulating material called ____________________ beneath their skins.
 

 

57. 

Mammals that lay eggs are known as ____________________.
 

 

58. 

The group of mammals with the fewest number of species is ____________________.
 

 

59. 

Pregnant female monotremes and marsupials lack a ____________________, which is an organ that passes materials between an embryo and its mother.
 

 

60. 

Humans, monkeys, and apes belong to the group of placental mammals known as ____________________.
 

 

Short Answer
 
 
ch-_13_birds_and_ma_files/i0650000.jpg
 

61. 

Identify structure A and explain its function.
 

62. 

Is the structure of the bird's bill, shown by B, adapted to sweeping underwater to search for food? Explain why or why not.
 

63. 

What is the organ indicated by C? How does the structure of this organ differ from the structure of the same kind of organ in an adult amphibian?
 

64. 

What is the organ indicated by D? What is its function?
 

65. 

Look carefully at the bird's foot, indicated by E. Do you think this bird paddles through water or perches on objects? Use the structure of the foot to explain your conclusion.
 

66. 

What type of feather is indicated by F? What is the function of this type of feather?
 
 
Characteristics of Bird and Mammals
Animal A
Animal B
Animal C
Cannot fly
Can fly
Can fly
Lays eggs
Lays eggs
Does not lay eggs
Has a diaphragm
Has  a gizzard
Has hair
Has webbed feet
Has webbed feet
Has webbed fingers
Has a bill
Has a bill
Has teeth
 

67. 

Is animal A a bird or a mammal? Explain your reasoning.
 

68. 

Is animal B a bird or a mammal? Explain your reasoning.
 

69. 

Is animal C a bird or a mammal? Explain your reasoning.
 

70. 

Decide whether each mammal in the table is a monotreme, a marsupial, or a placental mammal. Explain your reasoning.
 

71. 

Are any of the animals in the table ectotherms? Explain.
 

72. 

In which of the kinds of animals in the table do the females have mammary glands?
 

Essay
 

73. 

How do parent birds usually care for their eggs? Why is this care necessary?
 

74. 

Describe the path that blood follows through a bird's circulatory system. Begin with the right side of the heart. In your answer, explain where the blood picks up oxygen and where it releases the oxygen to the bird's body cells.
 

75. 

A gardener sees birds land in her garden. She worries that the birds may damage the plants. Why is it important to identify the birds before deciding whether to scare them away?
 

76. 

Describe the three types of flying and how much wing movement is involved in each.
 

77. 

If an animal does not have four legs, can it be a mammal? Explain.
 

78. 

What are two differences in the ways birds and most mammals reproduce and care for their young?
 

79. 

How are marsupials different from placental mammals?
 

80. 

How are monotremes similar to reptiles in the way that they reproduce? Identify three ways in which monotremes are different from reptiles.
 



 
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