A multi-week laboratory project has been developed to incorporate elements of student investigation, chemotactic behavior of protists, and genetic effects on chemotactic activity of Tetrahymena. The chemotaxis assay is based on spectrophotometric detection of protist-induced light scattering as cells migrate into a density gradient containing a known attractant. The three-week project consists of an introductory chemotaxis assay, investigation of dose-response effects, and culminates with the exploration of a Tetrahymena genetic mutant with known defects in motility. Additionally, this project incorporates a microscopic investigation of cellular structure and swimming behavior of mutant and wild-type cells. Students have responded well to the nature of the project, displaying clear understanding of the mechanism of the assay as well as the response of the protists to environmental manipulation and the molecular defects in the mutant cells.

中文翻译：

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一个多周的项目，在一个本科生生物学实验室检查四膜虫的趋化行为†

已经开发了一个为期数周的实验室项目，其中包括学生调查，原生生物的趋化行为以及对四膜虫趋化活性的遗传影响的要素。当细胞迁移到含有已知引诱剂的密度梯度中时，化学趋化分析是基于分光光度法检测由原生生物引起的光散射。这个为期三周的项目包括一个介绍性的趋化性分析，剂量反应效应的研究，并以探索运动性已知缺陷的四膜虫遗传突变体为终点。此外，该项目还对突变和野生型细胞的细胞结构和游泳行为进行了微观研究。学生对项目的性质反应良好，