Describes an experiment to characterize the enzyme polyphenol oxidase. Includes Purpose, Reagents and Equipment, Procedure, Extraction, Treatment of Data, and Discussion. (MA)

Describes the use of student-made photomicrographs as a source of student motivation and as a means for review of laboratory exercises in an introductory microbiology course. Includes an evaluation of this teaching method. (Author/MA)

Describes a demonstration that illustrates the reversibility of thermal reactions using a gas burner and copper sulfate. Explains the procedure and provides tips to guide student thinking. (DDR)

Describes a demonstration known as Elephant's Toothpaste in which the decomposition of hydrogen peroxide is catalyzed by iodide. Oxygen is released and soap bubbles are produced. The foam produced is measured, and results show a good relationship between the amount of foam and the concentration of the hydrogen peroxide. (DDR)

Introduces three demonstrations using rubber balloons: rate of reaction, air pressure, and solubility of gases in liquids. Provides the materials, procedure, questions, further investigation, and discussion in each demonstration. (YP)

The use of the thiosulfate ion in teaching the concepts of gas formation, precipitate formation, complex formation, acid-base interaction, redox interaction, time evolution of chemical processes, catalysis, and stoichiometry is discussed. Several demonstrations and activities are detailed. (CW)

Describes an experiment demonstrating Lenz's law by measuring a magnet falling through a copper tube compared to a nonmagnet falling. Presents diagrams and pictures showing the apparatus. (YP)

Outlines a laboratory activity which takes place at the zoo and helps make some of the important aspects of evolution more concrete. Includes the principles of adaptation, variation within a species, types of evolution, and predicting future evolutionary trends. Provides a student worksheet. (RT)

A study investigated the quantity of alloy lost in the fabrication of three types of cast restoration by dental students, and identified the proportion of loss at each of the four principal stages of the fabrication process. Suggestions for reducing metal loss and related costs in dental schools are offered. (MSE)

Described is the use of fluorometry in an experiment where the fluorescence of riboflavin is specifically quenched when titrated with riboflavin-binding protein. The amount of riboflavin, required by all organisms, in an unknown solution and the dissociation constant of the vitamin-protein complex can be determined using this method. (KR)

Gives advice on the legal necessity of safety planning for school science (or other) laboratories. Recommends looking into governmental definitions of the term "laboratory" to determine which educational activities should be covered by safety planning. (WRM)

Considers some consequences of altering intracellular calcium supply by magnesium concentration changes. Focuses on using this procedure as an exercise with allied health students as they witness therapeutic uses of magnesium and other calcium entry inhibitors. (DDR)

Describes a project in which students create wind machines to harness the wind's power and do mechanical work. Demonstrates kinetic and potential energy conversions and makes work and power calculations meaningful. Students conduct hands-on investigations with their machines. (DDR)

Describes how to determine the mass of a gas in a flexible, lightweight container and argues that the buoyant force of air needs to be taken into account. Recommends the use of mylar and describes equipment preparation. (DDR)

Reports on an ethnographic study of a molecular biology research laboratory called Sally's Lab. Portrays the social and cultural construction of a scientific community by studying the daily practices of the lab members and interpreting these observations. Concludes that there is not one set of experiences that pertain to all members within a given…