Chapter 34 Vertebrates

Question 1

What are the 4 main features of all chordates?

Answer 1

all chordates have a:
1) notochord
2) dorsal, hollow nerve cord
3) pharyngeal slits or clefts
4) muscular, post-anal tail

Question 2

What is a swim bladder?

Answer 2

The swim bladder is a buoyancy organ possessed by most bony fish. It is located in the body cavity and it contains gas (usually oxygen) ballast organ, enabling the fish to maintain its depth without floating upward or sinking.

Question 3

What are innovations of the primate group?

Answer 3

• primates have hands/feet, flat nails, fingerprints, short jaws, forward-facing eyes, and large brains
• humans have bipedalism, a larger brain, and reduced jaw compared with other apes
• used tools and walking upright saved energy

Question 4

Mammals

Answer 4

• have mammary glands, hair and fat, jaw
  part of middle ear, differentiated teeth, and are endothermic
• evolved from reptiles

Question 5

Reptiles

Answer 5

• have amniotic eggs, ribs for ventilation, and are ectothermic

Question 6

Birds

Answer 6

• are reptiles/evolved from reptiles

Question 7

Amphibians

Answer 7

• have four limbs descended from fins, moist skin that functions in gas exchange, and many live on both land and water