Frog Dissection Worksheet

  1. What do you think is the function of the nictitating membrane, and why?

  2. A frog does not chew its food. What do the positions of its teeth suggest about how the frog uses them?

  3. Trace the path of food through the digestive tract.  Name the organs IN ORDER in which the food would pass, starting with the glottis, and ending with the cloaca.  There are 6 total structures.

  4. Which parts of the frog’s nervous system can be observed in its abdominal cavity?

  5. Suppose in a living frog the spinal nerve extending to the leg muscle were cut. What ability would the frog lose? Why?

  6. The abdominal cavity of a frog at the end of hibernation season would contain very small fat bodies or none at all. What is the function of the fat bodies?

  7.  Structures of an animal’s body that fit it for its environment are adaptations. How do the frog’s powerful hind legs help it to fit into a life both in water and on land?

  8. During one mating of frogs, the female lays some 2,000 to 3,000 eggs in water as the male sheds millions of sperm over them. Why do you suppose female frogs lay so many eggs and male frogs produce so much sperm?

  9. Describe the two ways to determine the sex of a frog by external observation.  Make sure you identify the differences between the male characteristics and the female characteristics.

  10. How is the location of the external nostril openings and its eyes an advantage for an aquatic animal such as the frog?

  11. Describe the dorsal and ventral colorations of the frog.  What is the name for this type of coloring scheme?

  12. What is the scientific name of the American Bullfrog?

  13. Identify two peripheral organs that produce secretions for digestion, but do not have food and/or wastes moving directly through them.

  14. Describe the basic life cycle of a frog.  What is the name of the process that changes the larval stage of the frog into the adult stage?

  15. Identify the functions of the following internal organs of the frog.

16.  Label the diagram of the frog digestive system shown below: