Chapter 21 - Biodiversity of Vertebrates

Question 1

What 4 things do all chordata have

Answer 1

1. Dorsal hollow nerve cord
2. Notochord
3. Pharyngeal slits
4. Muscular post-anal tail

Question 2

Vertebrate characteristic evolution (from most primitive to most evolved)

Answer 2

1. Head (skull)
2. Vertebral column (backbone)
3. Jaws
4. Lungs
5. Lobed fins
6. Legs
7. Amniotic egg
8. Milk

Question 3

What are the 3 chordates that aren’t vertebrates?

Answer 3

• hagfish
• lancelets
• tunicates

Question 4

Hagfish

Answer 4

An outgroup of vertebrates.

• Does not contain a vertebral structure
• Lays eggs in water with no parental care

Question 5

Lampreys

Answer 5

The oldest living vertebrate

• Adults contain a vertebral structure
• Lays eggs in water with no parental care

Question 6

Chondrichthyans

Answer 6

Contain a vertebrae that is made of cartilage, NOT bone.

Ex. Sharks and rays

Question 7

Ray-finned fish

Answer 7

The first vertebrates to have a vertebrae made out of bone.

These fish are your basic every day fish types.

They are the most diverse vertebrate group.

Question 8

Lobe-finned fish

Answer 8

The most evolved of the fish since they use ( primitive) lungs to get oxygen.

Question 9

Are fish cold blooded or warm blooded?

Answer 9

Cold blooded

Proper term: ectothermic

Question 10

Amphibians

Answer 10

• First vertebrates to colonize land (some are aquatic some are terrestrial).
• First tetrapods (animals with 2 pairs of limbs)
• tend to dry out easily so they need to be in damp environments especially for reproduction

Ex. Frogs, salamanders

Question 11

Characteristics of an amniotic egg

Answer 11

Amnion -a fluid filled sac surrounding the embryo

Yolk sac - contains nutrients to feed the developing embryo

Shell - waterproof and allows for gas exchange

Prevents having to lay eggs in water^

Question 12

Reptiles

Answer 12

• First group to develop the amniotic egg.
• skin is covered with scales and waterproofed by keratin to protect it from drying out
• use lungs for gas exchange

Question 13

What are the largest living reptiles?

Answer 13

The crocodilians, which are crocodiles and alligators

Question 14

What group was the first vertebrates to live 100% of their life on land?

Answer 14

Reptiles

Question 15

Difference between reptiles and birds

Answer 15

Reptiles are cold blooded, with scales.

Birds are warm blooded, with feathers (homologous to scales) that allow them to fly

Question 16

What are the 3 major lineage of mammals?

Answer 16

Monotremes - egg layers

Marsupials - brief gestation

Eutherians - placental mammals