An experiment is described in which undergraduate students can optimize the relative yield of sec-butylbenzene by varying molar ratio and temperature. (Author/SA)

This undergraduate experiment shows that the inclusion of an appropriate additive can have a very marked effect on the physical properties of a polymer. The polymer used is polypropylene and the additives are 2-hydroxy-4-octyloxy-benzophenone and benzophenone. (BB)

Discusses the impact of using laboratory exercises and queries on developing student sensitivity to bioethical issues. Examples of these questions and the responses of students of an introductory life science course at Worcester Polytechnic Institute, Worcester, Massachusetts are presented. (HM)

Describes an apparatus that facilitates the quantitative study of fermentation in yeast by allowing simultaneous measurements of fermentation rates in several treatments and a control. Explains a laboratory procedure in which the apparatus is used. Several suggestions for further investigations are included. (Author/RT)

Outlined are materials and testing procedures in which various plant species are screened to determine if they are producing antibiotics. Diagrams are included. (RT)

Describes an experiment in which a simple laser-based apparatus is used for measuring the change in refractive index during the acid-catalyzed hydrolysis of glycidol into glycerine. Gives a schematic of the experimental setup and discusses the kinetic analysis. (MVL)

Discusses an enzyme kinetics laboratory experiment involving a two substrate system for undergraduate biochemistry. Uses the enzyme gamma-glutamyl transpeptidase as this enzyme in blood serum is of clinical significance. Notes elevated levels are seen in liver disease, alcoholism, and epilepsy. Uses a spectrophotometer for the analysis. (MVL)

Introduces a low-cost protein-testing technique using gel electrophoresis. Describes materials, manufacturing method, and experimental method. (YP)

An easily implemented practical exercise in applied science for biology students is presented that uses fungi to degrade an azo-dye. This is an example of bioremediation, the employment of living organisms to detoxify or contain pollutants. Its interdisciplinary nature widens students' perspectives of biology by exposing them to a chemical…

Contrary to popular belief, plants are very much in tune and in time with their immediate environment. The most important environmental cues for plants are light and gravity. In this article, the authors discuss the effects of light on plant development and use the spores of the sensitive fern (Onoclea sensibilis) in laboratory exercises to…

A project involving the synthesis of several naturally occurring copper double salts using simple aqueous conditions is reported. The ions present in the compound are analyzed using colorimetric, gravimetric, and gas-analysis techniques appropriate for the first-year laboratory and from the percent composition, the empirical formula of each…

In this article, the authors present a classroom experiment that was developed to introduce middle school learners to the carbon cycle. The experiment deals with transfer of CO[subscript 2] between liquid reservoirs and the effect CO[subscript 2] has on algae growth. It allows students to observe the influence of the carbon cycle on algae growth,…

Stomata are the pores on leaves through which carbon dioxide, oxygen, and water vapor are exchanged with the atmosphere. Researchers have found that leaf stomatal densities change in response to several environmental variables, including humidity, light intensity, and atmospheric levels of carbon dioxide, a greenhouse gas (Van Der Burgh, Dilcher,…

Describes a summer course in chemistry conducted by college teachers for children aged 9 through 12. The children were provided with simple laboratory equipment and performed actual experiments and recorded the results. A few demonstrations were given, but lecturing was kept to a minimum. (MLH)