Connor D. Holzer, Noah S. Leibold


This presentation was given live via Zoom at 1:00 p.m. (Eastern Time) on Wednesday, April 22.

This project reflects research conducted as part of a course project designed to give students experience in the research process. Course: BIO 421 P1



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Biogenically constructed calcium carbonate is one of the most utilized raw materials in the modern world. Used in areas such as construction, pharmaceuticals, animal feed, electrochemistry, plastics manufacturing, and development of bioarmor. The usage of biological materials in a variety of industries is rapidly becoming commonplace especially with the societal movement towards sustainability and sustainable materials. One common biomaterial is that of the mollusc shell. Our research focuses on how the Eastern oyster, Crassostrea virginica, deposits shell. While the scientific literature is replete with reports on structure and composition of oyster shell, it is still uncertain where materials are synthesized within the oyster and more importantly how they are transported and assembled at the shell formation front. Elucidating the processes of synthesis, transport, and assembly are key aspects to understanding the mechanism of shell biomineralization. Expanding upon the previous research, the present study builds upon the potential role of oyster blood cells, specifically hemocytes, as participants in the complex process of shell formation.An exploratory notch-repair study was conducted to assess cellular hemocyte changes over a seven-day sampling period. All experimental oysters were notched on Day 1 and hemolymph samples were harvested every twenty-four hours for seven days; control (un-notched) hemolymph was also harvested at each timepoint. Hemocyte concentrations were determined using hemocytometry, and images of repair shell were taken at each time point. Our hypothesis is that total hemocyte counts will vary over the seven-day repair period as shell repair/deposition occurs.Our results show a significant decrease in hemocyte concentrations from days one through four and a robust overall fluctuation in cell numbers over all seven days following localized shell damage. These changes in hemocyte numbers suggest that cellular components of oyster blood may be participating in shell deposition/repair in damaged oysters. This research demonstrates a possible correlation between total hemocyte counts and the onset of visible shell repair in notched oysters. Additional research is warranted in order to more clearly understand the role of hemocytes in shell deposition.

Publication Date


Project Designation

Course Project

Primary Advisor

Karolyn M. Hansen

Primary Advisor's Department



Stander Symposium project, College of Arts and Sciences

United Nations Sustainable Development Goals

Life Below Water; Industry, Innovation, and Infrastructure

A Cyte to See: An Exploratory Investigation of Hemocytes and Cellular Biomineralization in Crassostrea virginica