1. Subphylum:Vertebrata Class: Amphibia
AMPHIBIANS
Phylum: Chordata
Subphylum:Vertebrata
Class: Amphibia

2. Tropical, no appendages Salamanders and newts Frogs and toads
Order
Gymnophiona
Caudata
Anura
Common examples
Caecilians
small group, worm like,
Tropical, no appendages
Salamanders and newts
Frogs and toads

3. Digestive System Digestive system: Complete Most are carnivores
First animals with a “true” tongue (modified in anurans into a flip-and-grab feeding mechanism)
Have vomerine and maxillary teeth used for holding food rather than chewing.
Like the fish, have a common opening to the digestive, reproductive and excretory systems called the cloaca.

4. Respiratory System
Larva have gills
Adult have lungs controlled by a buccal pump
Skin – cutaneous respiration

5. Adults also use cutaneous (across the skin) respiration and buccopharyngeal (inside the mouth) respiration.
Disadvantage of amphibian respiration is that gas exchange can’t increase when metabolic demands increase.

6. SKIN Smooth and glandular (needed to keep skin moist)
Many give off toxic chemicals
Caecilians have folds in skin look like segments

7. External anatomy and skeleton
Long flexible vertebrae
Possess a tail except anurans which have their caudal (tail) vertebrae fused into urostyle
4 limbs except caecilians, anurans have very strong, long hind legs

8. Circulatory System
Double looped; systemic=to the body pulmonary= to the lungs
Three chambered heart: 2 atria and 1 ventricle
a spiral valve helps divide and direct blood from the ventricle into either the pulmonary & systemic systems

9. Temperature Regulation
Ectothermic and usually nocturnal
Behavior is to stay in moist, cool area during hot part of the day, occasionally bask in the sun to increase body temperature.
Tolerates a wide range of temperatures

10. Nervous System :
Forebrain (cerebrum): smell, color changes and visceral functions
Midbrain: sight, also assimilates sensory information
Hindbrain : motor coordination (movement); also regulates heart rate and respiration
Possess lateral line system

11. Chemoreception: through the nasal area, mouth and skin
Sight: binocular vision which allows for depth perception
Nictitating membrane to protect eye
Hearing: tympanic membrane; well developed in Anurans, poorly developed in Caudata

12. Sounds Vocalizations in anurans
Advertisement call: male to female, usually amplified by the male’s vocal sacs.
Reciprocation call: female back to male
Release call
Distress call

13. Excretory System :
Nitrogenous waste in aquatic forms is ammonia, In terrestrial forms is urea
Major problem is osmoregulation (controlling water loss)

14. Reproductive system: Dioecious Most have internal fertilization
Anurans have external fertilization, they use amplexus (copulatory grasp so male can stimulate female to release eggs that are then fertilized)