On the Cutting Edge: Frog Internal Anatomy Exploration
Frogs are excellent organisms for studies involving animal development, physiology, anatomy, and behavior. They are commonly studied in biology classes as representative vertebrates, but they also exhibit some specialized amphibian features. Introduce your students to the frog’s external anatomy using the dissection guide below and explore several interesting structures and their functions.
Frog dissection guide
- Examine the frog’s external features. This vertebrate animal represents a transition from an aquatic lifestyle to a terrestrial one. Notice the appendages developed for a terrestrial life. The frog is a tetrapod, meaning that it possesses 4 limbs for locomotion. Observe that each forelimb is divided into an upper arm, forearm, and hand. Each hind limb is divided into a thigh, lower leg, and foot.
- Study the head’s external features. Find the 2 nostrils at the head’s tip. They are used for respiration. Posterior to the eyes are tympani, the frog’s external sound receptors.
- Study the eyes. The frog has immovable eyelids, but the eyes may be covered with a nictitating membrane that moistens and protects them.
- Locate the cloaca at the specimen’s posterior end. The cloacal opening, or anus, is the single exit from the urinary, reproductive, and digestive systems.
- Place the frog on its dorsal side and pin its legs down. Cut through the jaw joints at the mouth’s sides and open the mouth wide.
- Identify the glottis and the opening to the esophagus. The esophagus leads to the stomach. The glottis leads to the lungs.
- There are 2 sets of teeth, an outer layer of maxillary teeth and the vomerine teeth, which are found behind the mid-region of the upper jaw.
- Two openings can be seen on the lateral sides of the mouth’s roof. These are openings to the Eustachian tubes, leading to the tympani. These tubes help equalize pressure.
The next step
Now your students are ready to learn about the frog’s internal anatomy, and our Advanced Frog Dissection BioKit® is a great resource to help them learn it. The kit includes 15 double-injected Carolina’s Perfect Solution® frogs, 15 disposable dissecting trays, 15 self-locking storage bags, and a detailed teacher’s manual including Carolina™ Bioreview® Sheets and blackline masters for reproducible student guides.