AMPHIBIANS

Amphibians What does the name amphibian mean? Why were they given this name?

Characteristics Describe the physical features of amphibians.

Ectoderms Amphibians are ectoderms. What does this mean and how does this effect their lifestyle?

Metamorphosis of amphibians Handout Compare and contrast the key physical features of a frog and a tadpole. Describe the difference between the frog’s life cycle and a salamander’s.

Heart What is the evolutionary advantage of the 3-chambered heart over the 2-chambered heart of fish? Trace the pathway of blood through the 3-chambered heart. \Why is the skin more important than the lungs in gaseous exchange? Why must the skin stay moist? What is the difference between toads and frogs concerning the skin?

Senses What is the tympanic membrane? Why is the sense of heart important to frogs? Why do the eyes protrude from the tops of their heads?

Reproduction Describe the process of reproduction in amphibians? Why must the eggs be laid in water?

Mating What are vocal cords? What is there purpose? Describe the process of producing sound?

Tongue Describe the tongue and its special adaptation for the frog.

Diversity of Amphibians Order Anura – frogs and toads Order Caudata – salamander What is the difference between a salamander and a lizard? Order Caecilians – limbless amphibians - Salamander – long slender body that resembles lizards - smooth moist skin and lack claws

Adapting to land What were some of the problems faced by amphibians as they made the transition to land? How was each problem dealt with in the body’s design? What trait of the salamander was an inadequate adaptation for life on the land?