Amphibians

Question 1

What did amphibians evolve from?

Answer 1

Lobe-finned fishes called crossopterygians

Question 2

What period did amphibians appear in?

Answer 2

The late Devonian period

Question 3

What are characteristics of amphibians?

Answer 3

• cold blooded
• use gills, lungs, skin, and mouth cavity in respiration
• moist, smooth, thin skin with no scales
• webbed feet
• lack claws

Question 4

What is metamorphosis?

Answer 4

When amphibians change from an aquatic larval stage to a terrestrial adult form

Question 5

What are states of inactivity known as?

Answer 5

• Hibernation when it occurs in the winter
• Estivation when it occurs in the summer

Question 6

Differentiate between larvae and adults

Answer 6

Larvae
- have two-chambered hearts

Adults
- have three-chambered hearts and well-developed circulation

Question 7

Why do amphibian eggs need to be laid in water?

Answer 7

Eggs lack multicellular membranes or shells. They are usually laid in water or in a moist environment and fertilized externally so they don’t dry up and die

Question 8

What are the orders of Amphibia?

Answer 8

Anura – Frogs & Toads
Urodela – Salamanders
Trachystoma – Mud eels
Apoda - Caecillians

Question 9

Differentiate between frogs and toads

Answer 9

Frogs
smooth, wet skin

Toads
dry, warty skin