Tetrapods

Question 1

Where did tetrapods evolve from?

Answer 1

Lobe-finned fishes

Question 2

Three characteristics showing that Amphibians are still aquatic

Answer 2

1. Reproduction happens in water; mostly external fertilization
2. Eggs are un-protected and hatch larvae with gills not lungs
3. Skin is thin, moist, and permeable

Question 3

Three characteristics showing that Amphibians are becoming terrestrial

Answer 3

1. Tetrapod skeleton grows strong, spine becomes more rigid
2. Loss of lateral line and development of sound and olfaction reception
3. Develop head mobility and a tongue to handle food within mouth

Question 4

Apoda or Caecilians

Answer 4

• Snake like
• Most blind as adults
• Breathe by skin and lungs

Question 5

Which amphibian reproduces internally?

Answer 5

Apoda (tadpole-like larva)

Question 6

Caudata or Urodela

Answer 6

Salamanders (with tail)

• Respiration by gills as young
• Respiration by lungs + skin as adults

Question 7

Anura or Salientia

Answer 7

Frogs and toads

- NO paedomorphosis

Question 8

Paedomorphosis

Answer 8

Retention of larval morphology after reaching adulthood (no metamorphosis)

Question 9

Which amphibian goes through paedomorphosis?

Answer 9

Salamanders

Question 10

Frogs vs. Toads

Answer 10

Frogs: thinner skin, attached to water, produce masses of eggs, normally jump

Toads: drier bumpier skin, less dependant on water, produce line of eggs, normally crawl

Question 11

In frogs & toads; what is the male’s part in fertilization?

Answer 11

The male attaches to the female’s back while she lays eggs; adds seminal fluid

Question 12

5 main innovations for reptiles

Answer 12

1. Egg with amnion
2. Dry scaly skin
3. Excretion of uric acid
4. Copulatory organ
5. Better jaws + stronger skeleton

Question 13

Anapsids

Answer 13

0 temporal openings

Question 14

Synapsids

Answer 14

1 temporal opening

Question 15

Diapsids

Answer 15

2 temporal openings

Question 16

What reptiles are anapsids?

Answer 16

Turtles

Question 17

What reptiles are synapsids?

Answer 17

Several extinct reptiles + therapsids

- Dimetrodon

Question 18

What reptiles are diapsids?

Answer 18

• Lizards
• Crocodiles & alligators
• Snakes
• Birds

Question 19

Birds main adaptions

Answer 19

• Feathers
• Skeleton; flight muscles
• Temperature regulation
• Respiration
• Reproduction and behaviour

Question 20

Birds: Feathers

Answer 20

• Derived from reptile scales

Question 21

Birds: Skeleton; flight muscles

Answer 21

Bones are porous, light and strong

- vertebrate fused to ribs and skull is fused in one piece

Question 22

Birds: Temperature regulation

Answer 22

Endothermic: body generates its own heat
Homeothermic: body maintains a constant temperature

Question 23

What are the first known mammals?

Answer 23

morganucodontids

Question 24

Origins of mammals

Answer 24

Descendants of Therapsids

Question 25

What differentiates a mammal from other vertebrates?

Answer 25

1. Major skull and dentition modifications 2. Ear apparatus 3. Hair, lactation 4. Changes in limb posture

Question 26

Prototherians

Answer 26

- Order Monotremata - Platypus & Echidna - 1 cloaca - pouch - absence of nipples - lactation

Question 27

Platypus

Answer 27

- Protherian - Order Monotremata - Semi-aquatic - Produces venom via crural system (only males) - Electro and mechanoreceptors on bill and skin

Question 28

Echidna

Answer 28

- Protherian - Order Monotremata - Mechano and thermoreceptors - Mucus glands - Curls in ball

Question 29

Metatherians

Answer 29

- Short gestation period - Inefficient placentas - Extremely altricial babies - Marsupials (pouch) - long lactation period - Hair e. g. Kangaroo

Question 30

Eutherians

Answer 30

- Some don't have hair as adults - Altricial or precocial babies - Short lactation period - Complex and advanced social behaviours

Question 31

Birds: Respiration

Answer 31

- Well-developed lungs and blood irrigation - With air sacs (hold fresh air) - Fly

Question 32

Birds: Reproduction & behaviour

Answer 32

- Well-developed brain for flight and visuals - High developed behaviour and visual displays during mating - Females only have left ovary

Question 33

Flightless birds

Answer 33

- Evolved from several independent origins - Most usually, evolved as a response to lack of land predators - Pelvic bones enlarged and sternum reduced e. g. Ostrich

Question 34

Seabirds

Answer 34

- Less colorful - Waterproof feathers - Live longer, reproduce later - Salt glands - Lost ability to fly - Wings shaped as fins

Question 35

Reptiles: Egg with amnion

Answer 35

Thin membrane with fluid that protects the embryo

Question 36

Reptiles: dry scaly skin

Answer 36

Heavier, thicker, non permeable - Protect against desiccation - Formed from epidermis

Question 37

Reptiles: excretion of uric acid

Answer 37

Highly concentrated urine | - Minimizes loss of water

Question 38

Reptiles: copulatory organ

Answer 38

Internal fertilization is now necessary | - Reproductive organs in cloaca

Question 39

Reptiles: Skeleton

Answer 39

More efficient for chewing and bigger prey (jaws) | - Larger and heavier bodies