Tori Johnson
Kylie Pocrnich
December 17, 2012
Zoology
In this lab, my partner Kylie and I will be examining the internal and external features of the clam. “Like all mollusks, a clam has a mantle which surrounds its soft body. It also has a muscular foot which enables the clam to burrow itself in mud or sand” (Miller and Levine). Clams are mollusks with two valves also nickname the bivalves. Clams are mostly marine animals however; the clams we will dissect are freshwater clams. Adult clams have bilateral symmetry but when they are larva clams have radial symmetry. A clam has complete digestion and has open circulation. The materials used in this lab were a preserved clam, a dissection pan, bent tip probe, scalpel, specimen bag, pins, gloves, tools, paper towels, goggles, ruler, lab coat, etc. In Miss Sido`s lab prep she went over the lab packet, taught us how to set up for dissection by getting only the certain tools needed, having paper towels in the pan, and she taught us how to properly clean up after dissection. She performed a lab dissection demo, where she showed us how to properly dissect the clam and also gave us a few tips. Some external methods Kylie and I did were lining the pan with paper towels, kits, body bag, measuring the clam and seeing how old our clam was. Our clam was 4” by 3” in size and it was 15 years old. The internal methods consisted of; cutting of the anterior and posterior adductor muscles in order to pry the shell apart dorsal side up. Opening the shell was very hard and required a lot of muscles! Once we were in the clam we removed the top of the mantle, the top set of gills, we shaved a few layers of the visceral hump off in order to expose the organs. We also pierced the pericardial cavity to expose the heart. Once all of that was done Miss Sido gave us an “organ tour” and showed us all the organs and where they were located. After that we drew a picture and labeled all of the organs and structures. Then we