Class Amphibia

Question 1

What kind of group is class amphibia and what species does it include?

Answer 1

• monophyletic group that includes frogs, salamanders, and caecilians

Question 2

How do amphibians respire?

Answer 2

they have thin, permeable skin and thats how they do gas exchange
- some have buccal pumps which are similar to lungfish to inflate their lungs because they don’t have ribs and air is drawn into the oral/throat cavity though nostrils or mouth and then they seal up and oral/throat cavity contracted to face air into lungs

Question 3

What is the life cycle of an amphibian?

Answer 3

their eggs lack shells and their embryos are sensitive to desiccation
- they undergo internal fertilization and have aquatic larvae and terrestrial adults
their larvae have gills and lateral line systems (they don’t look like adult)
- amphibians are not still fully adapted to life on land, they rely on water for reproduction

Question 4

Can you think of any parallels here with plants in terms of not fully terrestrial ? which ones?

Answer 4

ferns and mosses aren’t fully terrestrial and the sperm need water to travel to the egg and the frog’s larvae need water to grow to be a frog

Question 5

What are 3 orders of amphibians?

Answer 5

1. order anura
2. order urodele
3. order apoda

Question 6

What species include order anura?

Answer 6

frogs and toads (toads are frogs with leathery skin)

Question 7

What are some classifications of order Anura?

Answer 7

• they have hind legs modified for jumping
• lack tail in adult stage
• lack legs in early larval stage

Question 8

How do order anura reproduce?

Answer 8

eggs remain in their reproductive tract and hatch as tiny froglets (ovoviviparous and viviparous) reproduction

• they take care of eggs and tadpoles by carrying them on their back or in their mouth or stomach
• their embryos can develop without drying out

Question 9

how do order anura avoid predators?

Answer 9

they have poison glands behind their eyes and some of them are just poisonous

Question 10

what do order anura feed on?

Answer 10

they feed on algae as larvae and invertebrates as adults

Question 11

How do order anura feed? how do they eat?

Answer 11

frogs have a long sticky tongue in front of their mouth and its shot out using hydraulic pressure
- other annurans prey by pouncing on prey and then stuffing it into their mouthes

Question 12

which species include order Urodela?

Answer 12

salamanders and newts

Question 13

What are some characteristics/habitat of order Urodela?

Answer 13

• they are predators of invertebrates
• their larvae have external gills
  some adults remain aquatic like newts
  some adults become terrestrial but environment must be damn to keep their skin moist

Question 14

How do urodela walk?

Answer 14

• salamanders move side to side (similar to fish ancestors)
• legs are lateral and backbone is long … they can move slowly on land
• their legs are less energetically efficient vs human legs that are directly below pevis (erect)

Question 15

What are some characteristics of order Apoda?

Answer 15

• aka caecilians
• they are lego less (as a secondary adaptation)
• they had tiny eyes, can’t hear, thick skull and start teeth
  they mainly burrow and live in network of tunnels underground

Question 16

what is causing the global amphibian decline? and why is that important?

Answer 16

amphibians indicate the health of the earth
- possible causes include acid rain, habitat destruction, chytrid fungus, pollution, climate change and parasitic tapeworms