Ch 34 Chordates - Mammals Flashcards Preview

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Flashcards in Ch 34 Chordates - Mammals Deck (55):
1

Synapsids were the first what?

Amniote group to diversify widely into terrestrial habitates

2

What were the dominant amniotes during the Permian period?

Synapsids

3

Anapsid

No temporal openings in the skull for muscle attachment

4

Diapsids

Two temporal openings in the skull for muscle attachment

5

Are reptiles anapsids, diapsids, or synapsids?

Diapsids

6

Were the earliest amniotes anapsides, diapsids, or synapsids?

Anapsids

7

Synapsids

One temporal opening in the skull for muscle attachment

8

Are mammals anapsids, diapsids, or synapsids?

Synapsids

9

Shared derived characteristic of mammals

Hair

10

How do mammals nourish their young?

Milk produced by mammary glands

11

Are mammals endothermic or exothermic?

Endothermic

12

What modification in mammals transmits sound in the middle ear?

Three bones of the skull

13

Mammals have what kind of heart?

Four-chambered

14

Mammals have what kind of metabolic rate?

High

15

Hairs

Composed of dead, keratin packed cells of the epidermal skin layer

16

How does hair grow?

By proliferation of cells at its base in the hair follicle

17

Molt

The shedding of all hairs at once

18

Benefits of hair

1) Buoyancy
2) Concealment
3) Insulation
4) Protection
5) Sensing
6) Signaling
7) Waterproofing

19

Guardhairs

Long, coarse hairs that overlie underhair

20

Underhairs

Dense, soft, insulating hair

21

Horns

Bones extension of the skull

22

What covers horns?

A sheath of keratin

23

Antlers

Solid bone

24

What covers antlers?

Velvet

25

Velvet

A highly vascular, soft skin

26

When are antlers covered by velvet?

During their growth phase

27

Are antlers shed?

Yes, annually

28

Are horns shed?

No

29

Sweat glands

Produce a watery fluid that cools the skin surface

30

Sebaceous glands

Consist of cells that rupture to release sebum that conditions skin and hair

31

Mammary glands

Produce nourishing milk

32

Scent glands

Have various function in chemical signaling including territoriality and mating

33

Heterodont

Teeth differentiated to perform specialized functions

34

Advances in mammalian locomotion

1) Limbs positioned under, rather than to the sides, of the body
2) Muscular diaphragm for inhalation, loss of abdominal ribs
3) Enlarged cerebrum for greater coordination

35

Three groups of mammals

1) Marsupials
2) Monotremes
3) Eutherians

36

Monotremes

Mammals that reproduce by laying eggs

37

Female monotremes possess what?

An abdominal pouch within which offspring complete their development after hatching

38

How are monotreme young fed?

From milk secreted by the mother's skin within the pouch

39

Marsupials

Pouched, viviparous mammals

40

When are marsupial young born?

At the embryonic stage of development

41

Where do marsupial young complete development?

In the abdominal pouch

42

How are marsupial young fed?

From the mother's nipples

43

Are most mammals, marsupials, monotremes, or eutherians?

Eutherians

44

How are eutherian young nourished during embryonic development?

Via a placenta

45

Placenta

A vascular connection within the uterus between the mother and embryo

46

Gestation

The period of development in the uters

47

How long can gestation last?

One to twenty-two months

48

What is seen between marsupials and eutherians?

Evolutionary convergence

49

Digitigrade

Mammals that walk on their digits (toes)

50

Are ungulates considered digitigrades?

Yes

51

Perissodactyla

The odd-toed ungulates

52

Ungulates

Hooved mammals

53

Characteristics that distinguish humans from other apes

1) Upright posture and bipedalism
2) Larger brains
3) Reduced jawbones and jaw muscles
4) Shorter digestive tract

54

The larger brains of humans are capable of what?

1) Language
2) Symbolic thought
3) Artistic expression
4) Manufacture and use of complex tools

55

Are living primates a part of the human ancestral lineage?

NO