Chap.34 (2)

Question 1

Amniotes

Answer 1

are a group of tetrapods whose living members are the reptiles, including birds, and mammals

Question 2

Derived Characters of Amniotes (5)

Answer 2

• Amniotes are named for the major derived character of the clade, the amniotic egg, which contains membranes that protect the embryo
• The extraembryonic membranes are the amnion, chorion, yolk sac, and allantois
• The amnion encloses the embryo in a fluid-filled sac that reduces the dependence of tetrapods on an aqueous environment for reproduction The amniotic egg was a key adaptation to life on land
• The amniotic eggs of most reptiles and some mammals have a shell
• Amniotes have other terrestrial adaptations, such as relatively impermeable skin and the ability to use the rib cage to ventilate the lungs

Question 3

The reptile clade includes (6)

Answer 3

the tuataras, lizards, snakes, turtles,
crocodilians, birds, and some extinct groups

Question 4

Reptiles characteristics (5)

Answer 4

• Reptiles have scales that create a waterproof barrier
• Most reptiles lay shelled eggs on land
• Fertilization occurs internally, before the eggshell is secreted
• Most reptiles are ectothermic
• some are endothermic

Question 5

Birds are endothermic

Answer 5

capable of maintaining body temperature through metabolism

Question 6

ectothermic

Answer 6

absorb external heat as the main
source of body heat

Question 7

Derived Characters of Birds (5)

Answer 7

• Weight-saving adaptations for flight
• wings with keratin feathers
• elaborate courtship rituals
• Fertilization is internal
• Eggs and the developing embryos inside must be kept warm through brooding by one or both parents

Question 8

bird Weight-saving adaptations (4)

Answer 8

lack of a urinary bladder, females with only one ovary, small gonads, and loss of teeth

Question 9

Flight requires (3)

Answer 9

a great expenditure of energy, acute vision, and fine muscle control

Question 10

The Origin of Birds (3)

Answer 10

• Birds probably descended from small theropods, a group of carnivorous dinosaurs
• Feathers evolved long before powered flight
• Early feathers might have evolved for insulation, camouflage, or courtship display

Question 11

Living birds belong to

Answer 11

the clade Neornithes
* Several groups of birds include one or more flightless species
* The ratites are all flightless birds

Question 12

ratites

Answer 12

are all flightless birds

Question 13

Mammals are

Answer 13

amniotes that have hair and produce milk

Question 14

Mammals are class….

Answer 14

mammalia

Question 15

Mammals derived characters (8)

Answer 15

• Mammary glands, which produce milk
• Hair and a fat layer under the skin for insulation
• Kidneys, which conserve water from wastes
• Endothermy and a high metabolic rate
• Efficient respiratory and circulatory systems
• A large brain-to-body-size ratio
• Extensive parental care
• Differentiated teeth

Question 16

By the early Cretaceous (140 million years ago), the three living lineages
of mammals emerged:

Answer 16

monotremes, marsupials, and eutherians

Question 17

Monotremes are

Answer 17

a small group of egg-laying mammals consisting of
echidnas and the platypus
* Females lack nipples and secrete milk from glands on their bellies; the
baby sucks milk from the mother’s fur

Question 18

Marsupials (4)

Answer 18

• include opossums, kangaroos, and koalas
• The embryo develops within the mother’s uterus and is nourished by the placenta
• A marsupial is born very early in its development
• It completes its embryonic development while nursing in a maternal pouch called a marsupium (in the front or rear of mother)

Question 19

eutherians (2)

Answer 19

• Compared with marsupials, eutherians have a more complex placenta
• Young eutherians complete their embryonic development within a uterus, joined to the mother by the placenta

Question 20

Derived Characters of Primates

Answer 20

• Most primates have hands and feet adapted for grasping, and flat nails instead of
  claws
• A large brain and short jaws
• Forward-looking eyes close together on the face, providing depth perception
• A fully opposable thumb (in monkeys and apes)

Question 21

The mammalian order Primates includes

Answer 21

• lemurs, tarsiers, monkeys, and apes
• Humans are members of the ape group

Question 22

three main groups of living primates

Answer 22

• Lemurs, lorises, and bush babies
• Tarsiers
• Anthropoids (monkeys and apes)

Question 23

Apes

Answer 23

includes gibbons, orangutans, gorillas, chimpanzees, bonobos, and humans
* Apes diverged from Old World monkeys about 25–30 million years ago

Question 24

monkeys (2)

Answer 24

• evolved in the Old World (Africa and Asia)
• In the New World (South America), monkeys first appeared roughly 25
  million years ago

Question 25

Humans are (2)

Answer 25

• mammals that have a large brain and bipedal locomotion
• The species Homo sapiens is about 200,000 years old, which is very
  young, considering that life has existed on Earth for at least 3.5 billion
  years

Question 26

Derived Characters of Humans (6)

Answer 26

• A number of characters distinguish humans from other apes
• Upright posture and bipedal locomotion
• Larger brains capable of language, symbolic thought, artistic
  expression, and the manufacture and use of complex tools
• Reduced jawbones and jaw muscles
• Shorter digestive tract
• The human and chimpanzee genomes are 99% identical