Phylum?

Chordata

7 Classes:

1. Agnatha Jawless fish

2. ChondrichthyesSharks, rays

3. OsteichthyesBony fish

4. Amphibia

5. Reptilia

6. AvesBirds

7. MammaliaMammals

Amphibia

What is an amphibian?

• A vertebrate that with some exceptions, lives in the water as a larva and on land as an adult.• Uses gills as a larva, uses lungs as an adult.• Lacks scales and claws.• Has moist skin with mucous glands.

Theory:• First amphibians to climb onto land probably resembled lobed-finned fish similar to coelacanth.

• The transition from water to land involved havinglegs, lungs to breathe air and protecting eggs from drying out.

Characteristics:

Feeding: Tadpoles – filter feeders or herbivoresAdults – Carnivorous

Respiration: Tadpoles – Gas exchange through skinand use of gills.Adults – Lungs

Circulation:

Excretion: Kidneys filter wastes from blood and formurine to be excreted.

Reproduction:

External fertilization in most species

Read on p 775 to fill in the blanks…

Movement: Larvae – wiggling their bodies and usinga flattened tail.

Adults: Salamanders – walk, run move with S-shaped curves.Frogs and toads – Hind limbs enable them to jump.Tree frogs – have disks on their toes that serve assuction cups for climbing.

Response:Hearing: Through tympanic membranes (eardrums)

Large eyes that can movearound in their sockets.Eye surface is protected bya transparent nictitating membrane. Located inside the regular eyelid. Protect eyes underwater and keep moist on land.

http://animal.discovery.com/tv-shows/river-monsters/videos/japanese-giant-salamander.htm

http://animal.discovery.com/tv-shows/other/videos/the-vanishing-frog-a-new-species.htm