FROG DISSECTION LAB
Name: ________________________
Background
Amphibians are unique in that they were the first in that they were the first group
of vertebrates to successfully exploit the terrestrial environment for a major
portion of their life cycle. In this following laboratory activity, you will first learn
about some of the important external amphibian characters and adaptations.
Then, you will learn about the internal anatomy and physiology of the frog
through dissection.
Objective
1. You will learn about the external and internal structure and function of a frog
and be able to relate the importance of particular frog characteristics.
Materials
Leopard Frog
Dissection Tray
scissors
scalpel
probes
forceps or tweezers
Procedure
1. Acquire a frog dissection specimen and other appropriate materials listed
above.
2. Observe the frog’s external anatomy and answer questions 1 through 4 below.
Have me check your answers before you continue with the dissection.
3. Lay the frog on its back in the middle of the dissection tray. Using a scalpel
and/or scissors make a vertical incision through the skin, starting in the
genital area and ending at the breast. Further, make a lateral incision across
the breast. Peel back the skin.
4. After viewing the muscles exposed, make similar incisions using the scalpel
and/or scissors to expose the body cavity. Be careful not to damage internal
organs when complete this step. If necessary use scissors to cut through the
humorous arm bone so that the arms will lie back out of the way.
5. Refer to page 643 and the surrounding pages to answer the questions 5 and
6.
Questions
1. Describe what the skin of amphibians is like and how particular characteristics
that the skin has are associated with specific functions of the skin.
2. How is amphibian skin of the ventral region adapted for helping frogs maintain
the appropriate water balance?
3. Being a bilateral vertebrate, amphibians are highly cephalized with a number
of sensory devices at their anterior end.
a. Discuss important visual characteristics of amphibians.
b. Discuss important auditory characteristics of amphibians. Do amphibians
only use their ears?
4. Like other animals amphibians require glucose (from prey) and oxygen.
a. Discuss the manner in which frogs capture their prey.
associated characteristics in your frog.
b. Discuss and diagram the manner in which a frog breathes.
Observe the
5. Draw and label the exposed internal organs of your frog focusing on the
digestive organs pictured on page 643. Briefly describe the function of the
stomach, liver, gallbladder, and small intestine. Cut open the stomach and
see if there is anything in there.
6. Using other text resources, find the frogs kidneys, reproductive organs, heart,
and lungs. Locate and label these in your drawing above as well.