Describes a lab designed to analyze the organic compounds found in an ordinary fast-food lunch. (ZWH)

Teachers often use demonstrations to prepare students for a science experiment. This article describes a demonstration method to ensure that students are not supplied with all the answers before the actual experiment and to help them to remain an active part of the science lesson. (ZWH)

Describes an experiment in which the incubation time to observe denitrification and other processes of the nitrogen cycle is reduced from 7-14 days to 24-48 hours. Presents calculations of processes in the nitrogen cycle in the form of a dichotomous key. (SAH)

Describes an alternative to teaching ecology by using bacteria to test competitor survival. Students observe a time-dependent selective killing of other unrelated bacteria by Pseudomonas aeruginosa. (SAH)

Describes the inexpensive and safe method of using roundworms in the classroom or laboratories. Because parasitic infections are so common, students should learn about worms. Provides statistics on just how many people have a worm infection in the world. Explains how to study living nematodes, and obtain and use earthworms. (Contains 13…

Details a laboratory experiment focusing on the relationship between the structure and function of the tracheary elements of the xylem. (MKR)

Presents a simple experiment to compare the performance of the PASCO Introductory Dynamics System with that of an Ealing student air track. Discusses the relative advantages of both. Concludes that for a wide assortment of motion activities in a low friction environment, or studies of frictional forces, the PASCO Introductory Dynamics System is a…

Discusses enzymes, catalysts, and factors that affect the rate of a chemical reaction. Presents activities based on enzyme action on hydrogen peroxide and lactose intolerance. (Author/JRH)

Explains how to apply India ink to observe phagocytosis and vacuole formation in Tetrahymena. Recommends this experiment for introducing students to microscope use. (YDS)

Presents a microbiology experiment on how to make soft pretzels with different flours and analyze the results using regression models. (Contains 12 references.) (ASK)

Introduces a chemical model illustrating the aspects of the second law of thermodynamics which explains concepts such as reversibility, path dependence, and extrapolation in terms of electrochemistry and calorimetry. Presents a thought experiment using an ideal galvanic electrochemical cell. (YDS)

Aims to determine the pollution content of the water at two locations on Buffalo Creek, Evington, Virginia, by examining the benthic macro-invertebrates that inhabit the test sites. (Author/YDS)

Describes a simple exercise in percolation theory that can be performed easily and quickly in a laboratory using paper and a hole punch. (Author/MM)

Describes a simple laboratory activity illustrating the chemiosmotic principles of active transport in yeast cells. Demonstrates the energy coupling mechanism of active a-glucoside uptake by Saccaromyces cerevisiae cells with a colorimetric transport assay using very simple equipment. (Contains 22 references.) (Author/YDS)

Describes an experiment on the use of problem-based learning. (Author/YDS)