Frog Internal Anatomy

Name: ______

Class Period: ______

•Work safely – safety goggles on at ALL TIMES

•Follow ALL directions and ASK if you don’t know what to do

•All remains thrown away – nothing leaves the room

•Frog in ziplock – get spray from me. Store in lab drawer

•All tools clean and dry – tool kits left open

•New, dry paper towel in pan

•Tables clean and dry

  • Place the frog in the dissecting pan ventral side up
  • Using forceps (or your fingers) lift up to loose-fitting skin. Cut and remove the skin as demonstrated in class and in the video. Be sure to cut all the way up and past the front legs.
  • Repeat with the muscle layer. Be sure not to damage the organs underneath by cutting too deeply. You may need to cut through bone as you pass the front legs.

Locate and carefully remove each of the organs below.

  1. Fat Bodies: Orange or yellow spaghetti shaped structures that store energy
  2. Peritoneum: Spider web like membrane that covers many of the organs
  3. Liver: Largest structure in the body cavity. Brown in color and has three parts or lobes. While no food actually passes through the liver, it does secrete a digestive enzyme called bile.
  4. Gall Bladder: Green sac below the liver used to store bile from the liver
  5. Heart: At the top of the liver. Left and right atriums on top and a single ventricle on the bottom.
  6. Lungs: Two spongy structures below the heart and liver
  7. Stomach: Curving from underneath the liver attached to the esophagus at the top and the small intestine at the bottom. Feel free to cut the stomach open to see what may be inside.
  8. Small Intestine: Leads from the stomach to the large intestine
  9. Large Intestine: Leads from the small intestine to the cloaca
  10. Cloaca: Leads from the large intestine to outside the frog’s body
  11. Kidneys: Two dark, oblong structures along the frog’s back that filter blood

Answer the following questions.

  1. What is the name of the membrane that covers and connects many of the organs?
  2. What is the name of the sac found under the liver that stores bile?
  3. The esophagus leads into what organ?
  4. Which is usually the largest organ in the body cavity?
  5. What is the bottom of the heart called?
  6. What structure leads from the stomach to the large intestine?
  7. What structure leads from the large intestine to outside the body?
  8. What are the structures that filter blood?
  9. What structures are used to store energy?
  10. What, if anything, did you find in your frog’s stomach?