1. Amphibians: The First Terrestrial Vertebrates
Chapter 19
Mrs. LaLone

2. Tetrapod – “four-feet” First True tongue Highly glandular skin
Secretions aid in protection
Prevents from drying out
Ectothermic
Excrete Ammonia or Urea

3. Feeding Habits Adult amphibians are Carnivores Larvae are herbivores
Use Jaws or tongue to seize prey
Larvae are herbivores

4. Respiration Cutaneous Respiration – Pulmonary ventilation
gas exchange across skin
Occurs on land or in water
Requires a moist surface
Pulmonary ventilation
Occurs by buccal pump mechanism
Muscles of mouth and pharynx create a positive pressure to force air into lungs

5. Nervous System 3 Subdivisions of Brain Forebrain Midbrain Hindbrain
Olfactory centers
regions that regulate color change & organ function
Midbrain
Contains optic tectum that processes sensory info
Processes visual sensory information
Initiates motor responses
Hindbrain
Motor coordination
Regulates heart rate
Orchestrates Respiration

6. Eyes Vision is one of the most important senses
Primarily sight feederse
Respond to movements of their prey
Except caecilians

7. 3 Orders of Modern Amphibians
Order Caudata – “bears tail” Salamanders
Order Gymnophiona – “naked like a snake” Caecilians
Order Anura – “without tail” Frogs & Toads

8. Order Caudata – Salamanders
“Newts”
Olfaction helps in prey detection
Possess a tail throughout life
Live in moist forest floor litter; caves
Have aquatic larvae
Some lay eggs on land
Internal fertilization (spermatophore; female picks up)

9. Order Gymnophiona – Caecilians
Olfaction – helps in prey detection
Blind
Worm like
Burrowers
Internal fertilization

10. Order Anura – Frogs & Toads
Diverse diet - Bullfrogs will prey on small mammals, birds, other frogs
Moist environments
Adults lack tails
External Fertilization
Aquatic eggs and larvae (tadpoles)
Undergo Metamorphosis (change from larva to adult)
Hear with Tympanic Membrane
3 Chambered heart – 2 atria & 1 ventricle
Frog vs Toad