Frog Dissection Review 1.What does a frog’s anatomy have in common with a human’s? Frogs have all the same body systems as people and most of the same organs! 2.How does a frog’s anatomy differ from a human’s? Frogs have: a cloaca three-chambered heart unique teeth no external ear third eyelid they are also cold blooded

Frog Dissection Review Objectives: Describe the appearance of various organs found in the frog Name the organs that make up various systems of the frog Discuss frog adaptations

Materials Preserved Frog Dissecting Tray and Paper Towels Dissecting Kit: pins, forceps, scissors, probe

Step One Determine frog’s sex: males have thick pads on thumbs; males are often smaller than females. Male is on the right

Step Two Locate external features of frog Mouth, external nares, tympani, eyes and nictating membranes

Step Three Cut the hinges of the mouth and open it wide Locate the structures inside the mouth: Vomerine teeth, Maxillary teeth, Internal nares, Tongue, Eustachian tubes, Esophagus, and Glottis. Vomerine Teeth Internal nares

Look for the opening to the frog’s cloaca, located between the hind legs. Cut from where hind limbs meet to jaw. Then cut through the breast bone and muscle.

Step Five Locate organs of digestive system: esophagus, stomach, small intestine, pancreas, liver, gall bladder, rectum, cloaca

Rectum Large Intestine

Step Six Locate the circulatory organs: veins and arteries, heart with right and left atrium and one ventricle

Male or Female Reproductive Parts Fat Bodies

Clean-Up Clean up tools Wrap-up frog and organs in a paper towel Hold frog and take off gloves and wrap gloves around frog Dispose of frog/gloves in trash can Put away tools Clean up any remaining debris Wash hands

Frog Anatomy Wrap-up What are the functions of the following organs: 1. Cloaca Organ that eliminates urine, feces and sperm/egg 2. Tympanum External eardrum of the frog; help with hearing 3. Nictating Membrane Third eyelid that protects while eating and under water 4. Vomerine Teeth Teeth located on roof of mouth that help grab on toprey

Finished identifying external organs and organs of the mouth? Quiz one another over the organs and their functions until everyone is familiar with them I will ask students within your group to either identify the organ or tell me its function so know your stuff.