The cannibalism and interspecific predation lab uses both T. thermophila and T. vorax. Morphogenetic change is addressed by observing the T. vorax shift from microstome to macrostome form. As part of the lab, stomatin, the transformation inducing subtance produced by T. thermophila is isolated using simple techniques that can easily be carried out in high school classrooms. The change in morphology is obvious even under relatively low magnification. The lab can be used to address chemical induction of morphological changes, evolutionary differences among different species within the same genus, and, since the macrostome forms consume their own species as well as other Tetrahymena species, inter- and intra-specific predation. The use of inexpensive digital cameras to record morphological changes and predation events adds enormously to student interest and enthusiasm for this exercise.
Organisms; Relationship of Structure to Function; Mechanisms of Evolution; Population dynamics; Diversity of Organisms; Growth and Survival of Organisms; Diversity and Adaptation of Organisms; Interorganismal Relationships; Species Variation
Next Generation Science Standards Relationships
High School: HS-LS2-6 | HS-LS2-8 | HS-LS3-2 | HS-LS3-3 | HS-LS4-2 | HS-LS4-3 | HS-LS4-5
NYS Science Curriculum Guideline Relationships
Key Ideas 1.1 | 1.2 | 1.3 | 4.1 | 4.3
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- Ryals PE, Bae S, Patterson CE. 1999. Evidence for early signaling events in stomatin-induced differentiation of Tetrahymena vorax. J.Eukaryot.Microbiol. 46 (1):77-83.
- Ryals PE, Buhse HE Jr, Modzejewski J. 1989. Lipid modification during cytodifferentiation of Tetrahymena vorax. Whole cell phospholipids and triacylglycerols of microstomal and macrostomal phenotypes. Biochim.Biophys.Acta 991 (3):438-444.
- Smith-Somerville HE, Hardman JK, Timkovich R, Ray WJ, Rose KE, Ryals PE, Gibbons SH, Buhse HE Jr. 2000. A complex of iron and nucleic acid catabolites is a signal that triggers differentiation in a freshwater protozoan. Proc.Natl.Acad.Sci.U.S.A. 97 (13):7325-7330.
- Yang X and Ryals PE. 1994. Cytodifferentiation in Tetrahymena vorax is linked to glycosyl-phosphatidylinositol-anchored protein assembly. Biochem.J. 298 Pt 3:697-703.