1. Amphibians Means “double life” Have thin, moist skin, most have 4 legs
Are able to live on land, but rely on water for reproduction
3 Groups – salamanders and newts, frogs and toads, and legless caecilians

2. Transport & Respiration:
have closed circulatory system with 3 chambered heart(1- blood from lungs, 1-blood from body mix into 1 which pumps back to body & lungs)
Results in mixing of blood – less efficient
Skin important in gas exchange – must stay moist

3. Amphibian Functions Have excretory system with kidneys to remove waste
Excretion:
Have excretory system with kidneys to remove waste
Regulation:
Amphibians are ectotherms – variable body temps “cold-blooded”
They get their heat from external sources
Have a dorsal hollow nerve cord with a complex brain and sense organs (eyes, nostril, tympanic membrane)

4. External Frog

5. Reproduction: Sexual reproduction with external fertilization.
Eggs must be laid in water or moist area because it lacks protective membranes & shell (loses water)

6. Growth and Development
Most Amphibians go through metamorphosis including an aquatic stage and a terrestrial stage.
Tadpole  Frog