Teacher and Student Guides

The chemosensory response lab addresses cell response to a variety of substances, from avoidance/attraction response to modification of ciliary beat, and presents optional sections to allow teachers to tailor module use to specific classroom levels. Middle school students examine the response of the cells to simple substances like herbs, spices, or citrus peel, some of which are provided with the kit, or they can design their own experiments to test the avoidance/attraction response to a variety of substances of interest to them. High school students can examine more sophisticated chemical responses, for example to GTP. This lab has been adapted for use in classes ranging from 4th/5th grade through AP biology.

Module Kit Request Form
Relevant Concepts

Cell Response to Environmental Stimuli; Interorganismal Relationships

Next Generation Science Standards Relationships

High School:

HS-LS2-6 Evaluate the claims, evidence, and reasoning that the complex interactions in ecosystems maintain relatively consistent numbers, and types of organisms in stable conditions, but changing conditions may result in a new ecosystem.

HS-LS4-5 Evaluate the evidence supporting claims that changes in environmental conditions may result in (1) increases in the number of individuals of some species, (2) the emergence of new species over time, and (3) the extinction of other species.

Middle School:

MS-LS1-1 Conduct an investigation to provide evidence that living things are made of cells, either one cell or many different and types of cells.

MS-LS-2 Develop and use a model to describe the function of a cell as a whole and ways parts of cells contribute to the function.

MS-LS1-5 Construct a scientific explanation based on evidence for how environmental and genetic factors influence the growth of organisms.

Elementary School:

1-LS1-1 Use materials to design a solution to a human problem by mimicking how plants and/or animals use their external parts to help them survive, grow, and meet their needs. 

4-LS1-1 Construct an argument that plants and animals have internal and external structures that function to support survival, growth, behavior, and reproduction.

4-LS1-2 Use a model to describe that animals receive different types of information through their senses, process the information in their brains, and respond to the information in different ways.

5-LS2-1 Develop a model to describe the movement of matter among plants, animals, decomposers, and the environment. 

3-LS4-2 Use evidence to construct an explanation for how the variations in characteristics among individuals of the same species may provide advantages in surviving, finding mates, and reproducing. 


●Almagor M, Ron A, Bar-Tana J. 1981. Chemotaxis in Tetrahymena thermophila. Cell Motil. 1 (2):261-268.

●Francis JT and Hennessey TM. 1995. Chemorepellents in Paramecium and Tetrahymena. J.Eukaryot.Microbiol. 42 (1):78-83.

●Hellung-Larsen P, Leick V, Tommerup N. 1986. Chemoattraction in Tetrahymena: On the Role of Chemokinesis. Biol.Bull. 170 (3):357-367.

●Hennessey TM. 2005. Responses of the ciliates Tetrahymena and Paramecium to external ATP and GTP. Purinergic Signal. 1 (2):101-110.

●Kim MY, Kuruvilla HG, Raghu S, Hennessey TM. 1999. ATP reception and chemosensory adaptation in Tetrahymena thermophila. J.Exp.Biol. 202:407-416.

●Kohidai L. 1995. Method for determination of chemoattraction in Tetrahymena pyriformis. Curr.Microbiol. 30 (4):251-253.

●Kohidai L, Lang O, Csaba G. 2003. Chemotactic-range-fitting of amino acids and its correlations to physicochemical parameters in Tetrahymena pyriformis–evolutionary consequences. Cell.Mol.Biol.(Noisy-le-grand) 49 Online Pub:OL487-95.

See our glossary for the terms used in the modules.