Amphibians

7th Grade Life science

Amphibian Characteristics

• From greek amphibios = double life• Ectotherms --Hibernation & Estivation• Moist smooth skin• 3 chambered heart as adults

Chordate Phylum

Animal kingdom

Subphylum Vertebrata

ClassAmphibians

Order = Caecillians

Order = Caudata(salamanders)

Order = AnuraFrogs and Toads

Caecillians

Salamanders

Frogs and Toads

Frog Life Cycle

MetamorphosisMeta = change / Morph = shape

Differences between Frogs and Toads

FrogsHighly permeable skin that generally needs to

stay very moist.

Toads• Have thicker skin and are better adapted to

life away from water.

American Toad

Frog Skeleton

Frog Anatomy

Tympanic Membrane

Nictitating Membrane

Dark Camouflaged Back

External Anatomy

• Nictitating membrane--clear eyelid • Tympanic Membrane-- separates the outer

environment from the inner ear.• Dark camouflage coloration

Mouth Anatomy

Tongue

Maxillary Teeth

GulletMandible

Digestive Tract• Mouth --> Pharynx --> Stomach --> Small Intestine -->

Large Intestine --Cloaca

• Small Intestine--nutrient absorption and digestion• Large Intestine--digests bacteria, reabsorbs water

and forms feces• Liver--produces bile for digestion• Gall Bladder--stores liver bile

Ventral Anatomy

Gall Bladder

Small Intestine

Liver

Frog Stomach

Ventral Frog View

Small Intestine

Liver

Fat Bodies

Frog Dorsal Cut

Circulatory System• 3 chambered heart (left/right atrium; ventricle)• Veins = Oxygen poor blood

Artery = Oxygen rich blood Right Atrium

Left Atrium

Ventricle