amphibian

a chordate animal in class Amphibia

Classifying Amphibians

live partly on land and partly in water; are mostly tetrapods; are divided into three orders: caecilians, frogs, and salamanders

tetrapod

an animal that has four limbs

caecilian

a legless amphibian in order Gymnophiona

Classifying Caecilians

members of order Gymnophiona; legless; generally burrowing; resemble earthworms; have characteristics of vertebrates

frog

a short-tailed, tailless amphibian in order Anura

Classifying Frogs

order Anura: by far the largest order of amphibians; often live in and near water; also inhabit drier areas; mostly return to water to breed and lay eggs

salamander

a lizard-like amphibian in order Urodele

Classifying Salamanders

in order Caudata; hatch from eggs in water; go through metamorphosis as they transition to a terrestrial or semiaquatic life

Amphibian Structure

have thin, moist, highly permeable skin: functions as a respiratory organ, secretes mucus when they are on land; lack a diaphragm: use the lower part of their mouths to pump air into their lungs; have a three chambered heart: two atria and one ventricle; are herbivores as young and carnivores as adults

cloaca

a single opening for the digestive, urinary, and reproductive tracts in birds, reptiles, amphibians, and some mammals

central nervous system

the portion of the nervous system consisting of the brain and spinal cord

peripheral nervous system

the portion of the nervous system consisting of the nerves and ganglia outside the brain and spinal cord

estivation

a state of dormancy that an animal enters into in response to high temperatures and arid conditions

hibernation

a state of inactivity and extremely low metabolism that an animal enters into in order to survive unfavorable environmental conditions

amplexus

the physical contact of a male and female amphibian that stimulates the female to release eggs into the water

Amphibians in the Environment

frog deaths maybe solved by fungus-resistant frogs; important part of both the food chain and their ecosystems