AMPHIBIANSKingdom: AnimaliaPhylum: Chordata

Animals with a backbone

Phylum Chordata

• Classes:– Amphibia– Reptilia– Aves– Chondrichthyes– Osteichthyes– Mammalia

General Characteristics• It is an animal in

Kingdom Animalia, Phylum Chordata, Class Amphibia

• Most lay eggs in WATER.

• It is an ECTOTHERMECTOTHERM – body temperature is determined by environment (opposite = Endotherm)

Salamander vs. Newt

Which one is an amphibian?

• Toad vs. Frog

What’s the difference?

Life Cycle

• Begin life as an Egg mass (Eggs are Moist, not Hard)

• Go through Metamorphosis

• Egg to Tadpole to Tadpole frog to Young frog to Adult frog

• External Fertilization

Respiratory System• Begin their lives with

gills and most end their lives with lungs.

• Some can breathe through their skin – their skin is permeable (allowing materials to flow in the frog to out of frog)

• So…how does the oxygen get in our blood?

Let’s take a look at Humans…

• 4 chambered heart• Very efficient• Let’s label…

– Right ventricle– Left ventricle– Right Atria– Left Atria– Aorta– To lungs (not oxygenated)– From lungs (oxygenated)– To body (oxygenated)– From body (not oxygenated)

Cardiovascular System

• Frogs have a 3 chambered heart

• Consisting of 2 atria and 1 ventricle.

• Lungs help to oxygenate the blood and also take out carbon dioxide

Digestive System• Mouth – break down of food• Gullet• Esophagus• Stomach – break down of food• Small intestine – food is

digested and absorbed• Liver makes bile; gall bladder

stores bile• Pancreas secretes enzymes to

break down food• Large intestine – water is

absorbed• Cloaca – excretes exit

Digestive System

• Accessory organs help to digest food

• Liver – makes bile• Gall bladder – stores

bile• Pancreas – secretes

enzymes to help with digestion

Excretory System

• Kidneys – remove toxins from blood

• Toxins travel through the ureter (tube) until it reaches the bladder.

• Bladder holds the urine until it is excreted through the cloaca.

Importance

• Amphibians help us to monitor the environment

• Check the handout for more information

Frog Malformations