Professor, Cell Biology
McGowan North, Room 213
General Biology I (Bio 191)
- Cell Biology (Bio 250)
- Capstone (Bio 395)
- Cell Biology for Teachers (SDV 421)
My lab is interested in understanding the ways in which cells can respond to changes in environmental conditions (e.g. light, temperature, water conditions) that allow them to remain ecologically successful. Specifically, we work with diatoms, a ubiquitous form of unicellular algae that exists in almost all freshwater and marine environments, and one of the few kinds of organisms that can successfully incorporate silicon, using it to form a hardened siliceous cell wall. While many forms of diatoms are planktonic, we work with sediment dwelling diatoms (i.e. benthic) that are able to move by a mucilage-based gliding mechanism. This gliding is regulated, for example allowing the cells to move into light regions (for energy) or out of the light (to avoid photodamage or to provide for better refuge). Our lab uses several kinds of microscopic observations and treatments to understand how characteristics and changes in light, surface, population, and water conditions affect and help regulate the ability of different diatom species to move and adhere.
Cohn, S.A. (2001) Chapter 13: Photo-stimulated Effects on Diatom Motility. In: Photomovement. D-P. Häder & M. Lebert (eds.) Comprehensive Series in Photosciences (D.-P. Hader, G. Jori, series eds.), Elsevier Pub, Amsterdam. Pp. 373-399.
Cohn, S.A., Farrell, J.F., Munro, J.D., Ragland, R.L., Weitzell, R.E. & Wibisono, B.L. (2003). The effect of temperature and mixed species composition on diatom motility and adhesion. Diatom Research 18:225-243.
Cohn, S.A., Bahena, M., Davis, J.T., Ragland, R.L., Rauschenberg, C.D. & Smith, B.J. (2004) Characterisation of the diatom photophobic response to high irradiance. Diatom Research 19:167-179.