Kingdom: Animalia
Phylum: Chordata
Subphylum Vertebrata
Class: Amphibia
Order: Anura
Genus: Rana Species: Rana pipiens
I. Purpose: To examine the frog externally and internally by dissection.
II. Materials: 1. Frog 2. Dissection pan 3. Manual 4. Dissection utensils
III. Methods: A. External: The dissectors set up for their lab by getting the following materials: the frog, dissection utensils, dissection manual, and the dissection pan. Dissectors placed the frog anteriorly with the dorsal side up. Dissectors noticed that the body of the frog was divided into 3 regions: the head, neck, and trunk. Dissectors also noticed that the frog had a smooth, protective skin. The skin contained mucus glands to keep it moist, and it also had pigment cells to regulate its color. Dissectors found 2 forelegs (which is made up of an upper arm, forearm, wrist, hand, and digits) on the trunk of the body. Dissectors also found the hind leg ( composed of the thigh, shank, ankle, foot, and digits) on the trunk of the body. The forelegs were located more anteriorly than the hind legs. Dissectors also noticed that the forearm had 5 digits while the hind leg only had 4 digits. The dissectors found 2 nostrils, nares, located on the anterior part of the head. Posterior to the nares, the dissectors found the eyes. The eyes had an upper and lower eyelid, as well as a third lid, the nictitating membrane (which covers the eye while the frog is swimming). Dissectors peeled a portion of the nictitating membrane off using the blunt probe. Dissectors found the tympanic membrane, the eardrum, just right behind the eyes. Dissectors opened the mouth of the frog with their hands, and made an extra posterior cut where the 2 jaws met with