1. Amphibians 7th Grade Life science

2. Amphibian Characteristics • From greek amphibios = double life • Ectotherms --Hibernation & Estivation • Moist smooth skin • 3 chambered heart as adults

3. Animal kingdom Chordate Phylum Subphylum Vertebrata Class Amphibians Order = Caecillians Order = Anura Frogs and Toads Order = Caudata (salamanders)

4. Caecillians

5. Salamanders

6. Frogs and Toads

7. Frog Life Cycle Metamorphosis Meta = change / Morph = shape

8. Frogs Highly permeable skin that generally needs to stay very moist. Toads Have thicker skin and are better adapted to life away from water. Differences between Frogs and Toads

9. American Toad

10. Frog Skeleton

11. Frog Anatomy Nictitating Membrane Tympanic Membrane Dark Camouflaged Back

12. External Anatomy • Nictitating membrane--clear eyelid • Tympanic Membrane-- separates the outer environment from the inner ear. • Dark camouflage coloration

13. Mouth Anatomy Maxillary Teeth Tongue Gullet Mandible

14. Digestive Tract • Mouth --> Pharynx --> Stomach --> Small Intestine --> Large Intestine --Cloaca • Small Intestine--nutrient absorption and digestion • Large Intestine--digests bacteria, reabsorbs water and forms feces • Liver--produces bile for digestion • Gall Bladder--stores liver bile

15. Ventral Anatomy Liver Small Intestine Gall Bladder

16. Frog Stomach

17. Ventral Frog View Fat Bodies Small Intestine Liver

18. Frog Dorsal Cut

19. Circulatory System • 3 chambered heart (left/right atrium; ventricle) • Veins = Oxygen poor blood Artery = Oxygen rich blood Right Atrium Ventricle Left Atrium