Describes simple quantitative determinations for ethanol and carbon dioxide, together with techniques for examining the effects of a number of environmental factors on their production. The experimental work centers around the growth of a cell population of yeast, and is suitable for senior high school students. (JR)

Presents an outline of current knowledge relating to the response of radicles to a directional source of water (hydrotropism). New techniques are described that may be used in biology classes to demonstrate the hydrotropic response in plants. (JR)