Activities that consider the courtship behavior and mating patterns of millipedes are presented. The functional significance of a behavior that has evolved through indirect competition between males is discussed. The procedures for seven experiments, results, and interpretations are included. (KR)

An activity simulating natural selection in which wild birds are predators, green and brown pastry "baits" are prey, and trays containing colored stones as the backgrounds is presented. Two different methods of measuring selection are used to describe the results. The materials and methods, results, and discussion are included. (KR)

Eleven demonstrations of light polarization are presented. Each includes a brief description of the apparatus and the effect demonstrated. Illustrated are strain patterns, reflection, scattering, the Faraday Effect, interference, double refraction, the polarizing microscope, and optical activity. (CW)

Describes an effective laboratory method for demonstrating bacterial flagella that utilizes the Proteus mirabilis organism and a special harvesting technique. Includes safety considerations for the laboratory exercise. (MDH)

Describes an experimental procedure that can be used to determine the potential bacterial contamination of stagnant water in emergency laboratory eyewash bottles. Contains 11 references. (WRM)

Reports on the design and testing of student-directed investigations for use in large enrollment biology courses. Describes a set of experiments that include the preparation and study of the enzyme tyrosinase. (DDR)

Details a lesson that utilizes trigonometric identities to determine the optimal angle between the atoms of covalent bonds. Generates a proof of the optimal angle for a molecule with four identical atoms bonded to a central atom that has a complete valence shell. (DDR)

Begins with the procedure and results from an investigation on the effect of fluoride on the reaction between eggshell (substitute teeth) and dilute ethanoic acid. Describes an elegantly modified and improvised apparatus. (DDR)

Provides an exercise designed to give students an appreciation for the genetic basis of behavior. Employs the phenomenon of glucose aversion as an example of evolution by mutation and accelerated natural selection, thereby revealing one of the ways in which organisms adapt to human interference. (DDR)

Introduces an investigative microbiology laboratory activity emphasizing critical thinking and experimental design in which students isolate and characterize a bacterium from a specific habitat. Explains the procedures of the laboratory including safety, sample collection, and isolation. (YDS)

Presents an experiment in which students use laboratory data to calculate the interphase mass transfer coefficient for a fluid passed over a sphere and obtain correlations for solid-gas mass transfer. Students develop a realistic mathematical model to describe the sublimation process. (DDR)

Recommends the use of a model of DNA made out of Velcro to help students visualize the steps of DNA replication. Includes a materials list, construction directions, and details of the demonstration using the model parts. (DDR)

Presents several variations on a demonstration in which alcohol vapors are combusted in large small-necked bottles, causing a blue flame to shoot from the bottle's mouth. Describes variations with different pure alcohols, temperature, alcohol/water solution concentration, oxygen concentration, type of container, and the addition of salt for color.…

Presents guidelines for stocking, organizing, and maintaining a storage space for physics education laboratory and demonstration equipment. (WRM)

Materials science can be taught by applying organic light-emitting electrochemical thin-film devices and in this method students were allowed to make a light-emitting device by spin coating a thin film containing ruthenium (II) complex ions onto a glass slide. Through this laboratory method students are provided with the opportunity to learn about…