Use of Transmission Electron Microscopy to Study the Minute Male Parts of a Freshwater Pond Snail (Physa gyrina)
Tammy J. Greevers* and Kristina A. Sit
Dr. George L. Shinn, Faculty Mentor
Species of freshwater pond snails are distinguished from each other by anatomical features of the male copulatory organs. Taxonomic descriptions of these structures are typically ambiguous: superficial aspects of form are described using only light microscopy. To allow precise comparisons with other species, we are using TEM to study the cellular construction of the penis sheath of Physa gyrina. The thick-walled glandular part of the penis sheath contains a single type of structurally elaborate secretory cells, microvillus-bearing support cells, and smooth muscle cells. The structural complexity of vesicles within the secretory cells, reveals that their product contains at least four chemically distinct components. The thin-walled membranous part of the penis sheath is dominated by a microvillar cells and smooth muscle. An important goal of our on-going study is to determine the fate of the secretions of the penis sheath. We suspect that they are transferred to females during mating.
Keywords: Transmission Electron Microscopy, Physa gyrina, Glandular Penis Sheath, Freshwater Snail Taxonomy
Topic(s):Biology
Presentation Type: Poster
Session: 8-9
Location: SUB-GEO
Time: 4:15