1. Vertebrates Amphibians

2. Characteristics Breathe Lungs and skin Skin Thin; must stay moist Absorb water and oxygen Eggs Must stay in water; young live in water

3. Double-loop circulatory system3-chambered heart! Why is the double-loop system more efficient than the single-loop system of the fish?

4. “Double-life” Metamorphosis Tadpole with tail and gills becomes adult without tail and gills Adults have lungs to get oxygen

5. First vertebrates on land… 3 Groups Frogs & toads Salamanders Caecilians

6. How are frogs and toads similar? How are frogs and toads different?

7. Warm up How is the frog’s skin like a lung?

8. What does it mean that amphibians are ectothermic?