Bullfrog Dissection

Class Amphibia

Group Anuran

No tail, skeleton adapted for jumping.



Ms. Spencer Jr's open for learning.

 Tetrapod

External Anatomy

Limbs
Digits - forelimbs have four digtis (fingers); hind limbs have five. The hind feet are webbed as an adaptation to swimming.
Amplexus - technical term for when frogs mate, the male grasps the female's trunk with his forelimbs.
Skin - used for repiration when warm and active, secretes a protective mucas which minimizes water loss.
Cloaca - located in the posterior abdomen, where the digestive/urogenital systems open.
Eyes - large, adapted to spot insects (diet).
Nictating Membrane - transparent eyelid which cleans/protects without blocking vision.
Tympanic Membrane - external eardrum, derived from lateral line organ, adapted to hear in aquatic and terrestrial environments.
Tongue - sticky, attatched to front of mouth (unlike humans), traps insects (diet).
External Nare - nostrils, connects to oral cavity.
Vomerine Teeth - located in roof of mouth, hold on to prey.
Glottis - located on floor of pharynx, opening to the respiratory system.
Eustaenian Tubes - connect to middle ear.

Inside the mouth - right in the center you can see the glottis.

Our massive she-bullfrog's underside!

Four digits on the forelimbs.

Hind feet are webbed - adaptation for swimming.

Eye and tympanic membrane - adaptation to aquatic/terrestrial environment.

Sticky tongue attached at the front (diet of insects).

Internal Anatomy

Liver - large, has three lobes
Gall Bladder - stores bile (made in the liver, breaks down fat) and passes it to the duodenum.
Esophagus - leads to the stomach, digestive system.
Stomach - pyloric valve separates from small intestine.
Small Intestine - relatively short because frog is carnivorous.
Rectum - opens into the cloaca.
Fat Bodies - yellow finger-like projections, store fat, floatation, warmth, energy.
Kidney - form concentrated urin.
Bladder - thin tranluscent sac, water actively reabsorbed from urine by the bladder.
Ovaries - located at anterior end of the kidneys, attatched to the body wall.

Under the layer of skin you can see the muscle.

The red shows oxygenated vessels - the inside of the skin.

Blue - unoxygenated.

Once the layer of muscle is removed...

Yellow finger-like fat bodies - floatation, warmth.

Where the eggs are - the ovaries.

 

Fat bodies - resemble tentacles...



Three lobes of the liver.

Liver in place - right, left anterior, left posterior.

The heart.

Small intestine.

Lungs - bullfrogs also breathe through their skin.

Stomach - pylorus - small intestine.

Guess what this is!

Very muscular thigh - hops, swims, propels!

A final look, thank-you Ms. Spencer Jr!