Vertebrates

Amphibians

CharacteristicsBreathe

Lungs and skin

Skin

Thin; must stay moist

Absorb water and oxygen

Eggs

Must stay in water; young live in water

Double-loop circulatory system3-chambered heart!

Why is the double-loop system more efficient than the single-loop system of the fish?

“Double-life” Metamorphosis

Tadpole with tail and gills becomes adult without tail and gillsAdults have lungs to get oxygen

First vertebrates on land…3 Groups

Frogs & toads

SalamandersCaecilians

How are frogs and toads similar?

How are frogs and toads different?

Warm up

How is the frog’s skin like a lung?

What does it mean that amphibians are ectothermic?