1. Amphibians
1st tetrapods

2. Classification Kingdom – Animalia Phylum - Chordata Class Amphibia
3 Orders
Anura (Frogs & Toads)
Urodela (Salamanders)
Apoda (Caecilians)

3. Characteristics Ectothermic 3-chambered heart (Double circulation)
Smooth skin, lacks scales (Desiccation if dry)
Cutaneous respiration
Lungs (Positive pressure mouth breathing)
Excretes urea
Lack claws on toes

4. Anura

6. In amphibians, the blood makes two passes through the heart.
Heart ---> lungs --> heart ---> body

8. Metamorphosis Tadpoles Frogs Herbivorous Carnivorous Aquatic
Aquatic & Terrestrial
Single loop circulation
Double loop circulation
Gills
Lungs

10. Amplexus

12. Frogspawn

13. Tadpole

15. Froglet

16. Frog Defenses

18. Bioindicators

19. Urodela
Salamanders
Newts (Efts)
Mudpuppies

22. Apoda