Presents a laboratory in which students are provided with cultures of three bacterial strains. Using the results, students will determine which of the strains corresponds to a mutant lacking a particular functional gene. (DDR)

Reports on a study that assesses the effects of the application of visual information-processing theory to the design of a laboratory manual for chemistry. Focuses on the effects on content learning, practical skill mastery, and attitudes of university students enrolled in a general chemistry course. Contains 41 references. (DDR)

Presents an exercise to demonstrate two fundamental concepts of fluid mechanics: the Reynolds number and the Principle of Continuity. The exercise demonstrates flow in a major blood vessel, such as the aorta, with and without a stenosis. Students observe the transition from laminar to turbulent flow as well as downstream persistence of turbulence.…

Presents the idea that several points should be considered in animal dissection: (1) ethics; (2) the animal's position; (3) the law; and (4) the actual benefits to society. Recommends that students be carefully prepared for animal dissection. Contains 21 references. (DDR)

Describes a design for a hand-held conductivity tester powered by a 9V battery that gives semi-quantitative results for aqueous electrolyte solutions of concentrations ranging from 0.001 M to 0.1 M. The tester uses a bar-graph LED driven by an LM3914 integrated circuit to indicate the level of conductivity. A list of parts, procedures, and results…

Presents a complete set of laboratory experiences on density. Includes establishing a density table, identifying an unknown, determining the density of irregular solids, and expanding the density table. Activities can be augmented with discussions about other applications. (DDR)

The advantages and justifications for using small animals in human-oriented research are reviewed. Some of the pitfalls of extrapolating animal-derived data to humans are discussed. Several specific problems with animal experimentation are highlighted. (CW)

Described is a laboratory experiment designed to expose students to problem-solving methods individually and as a group. Included are background information, a list of materials, laboratory procedures, analysis methods, and probable results. (CW)

Described are teaching methods used to teach measures of central tendency to middle and high school students. Discussed are quantitative and qualitative data, basic experimental terms, a general overview of data analysis, data charts for quantitative data, qualitative data analysis, and extensions for older students. (CW)

Presented is an experiment which provides a study both of the end correction involved with open pipes and also of the effect that varying the size of the tone hole in the pipe has on its fundamental frequency. Discussed are equipment, formulas, background, and methods. (CW)

Described are two microscale chemistry laboratory experiments including "Microscale Syntheses of Heterocyclic Compounds," and "Microscale Acid-Base Extraction--A Colorful Introduction." Materials, procedures and probable results are discussed. (CW)

Presented is a technique for making various molecular models from a strip of paper. Instructions for six models including tetrahedral, trigonal bipyramid, octahedral, pentagonal bipyramid, and capped octahedron models are provided. (CW)

Presented is an activity designed to introduce introductory chemistry students to the standard reduction potential table. Included are lists of equipment and reagents, procedures, sample worksheets, and teaching directions. (CW)

Described is an activity based on a fictitious poisoning incident that is designed to challenge gifted and talented high school students. Discussed are the laboratory procedures, reagents, instrumentation, and results. (CW)

Detailed is a method in which short pieces of teflon tubing may be used for collection tubes for collecting preparative fractions from gas chromatographs. Material preparation, laboratory procedures, and results of this method are discussed. (CW)