Name: Date: Period: Frog Dissection Lab Problem: What organs and organ systems can be observed in a frog. Hypothesis: (Remember to answer the problem in a complete sentence.) Alternate Assignment: (use to complete this lab report) http://www.mhhe.com/biosci/genbio/virtual_labs/BL_16/BL_16.html Materials: o Frog specimen o Dissection kit o Safety Glasses o Dissection tray Safety: Handle all specimens carefully and respectfully. Please be careful using both the scalpel and the scissors. Clean all equipment completely when finished. Specimens have been preserved in chemicals therefore safety glasses are required. Procedure: Draw a detailed image in each box below 1. External Anatomy Dorsal view: Ventral view: Describe the frog skin: Images and ideas from http://www.biologycorner.com/resources/dissection-‐cut.gif Name: Date: Period: 2. Internal Anatomy • • • • • Pin the frog ventral side up on the dissecting tray by pinning down each limb. Make an incision with the scalpel starting at the center between the forelimbs of the frog. Cutting down the center till you are between the hind limbs. Make sure all cuts are shallow as to not damage the underlying tissue. Make perpendicular cuts at the ends of the initial cut (see diagram). One incision is between the shoulders and the other incision is between the legs. Carefully the skin to the sides and pin it down. Observe the skin and how it can help in gas exchange for the frog. Make another incision following the same pattern as above going through the muscle tissue. Pin back the muscle tissue. Additional information: If the frog is female, there may be many dark colored eggs in the abdomen or if your frog is larger, there may be many spaghetti-like fat bodies. Observe both and then remove them to continue observing the rest of the abdominal cavity. Draw a detailed illustration of the internal anatomy of your frog. Label the following parts: Stomach, Small intestine, Large intestine, Liver, Pancreas, Gallbladder (under liver), Heart, Spleen, Lungs, Kidneys (near backbone), and Bladder. Conclusion: Use your observations to explain how your hypothesis is correct or incorrect. CLEAN UP: 1. Remove all dissected tissues and frog to front garbage can. 2. Completely clean and your dissection instruments and place them back in their container. 3. Clean the dissection tray. Images and ideas from http://www.biologycorner.com/resources/dissection-‐cut.gif