Suggests ways in which hens' egg vitelline membranes can be used to demonstrate cell traction effects. Reviews procedures for using and culturing the membranes and identifies topic areas for student projects. (ML)

Clearing is a simple and rapid technique in which 75 percent lactic acid is used to remove pigments and cytoplasmic contents of fresh leaves, enabling microscopic view of various internal leaf layers. Procedures for using the technique (which helps students gain a more thorough understanding of plant anatomy) are given. (DH)

Presents a classroom experiment that demonstrates the directional sensitivity of the human ear. Outlines the activity's procedures and provides a diagrammatical view of the experimental arrangement. Also included is an analysis of the expected results. (ML)

Thin slices of potato can be used to demonstrate the presence of protein, carbohydrates, and nucleic acids at the cellular level. Procedures and materials are provided for these simple tests. Also indicates that the presence of fat can be readily seen by staining avocado with Sudan red or Sudan black. (Author/DH)

Briefly describes some of the more recent developments in the use of human hairs for such instructional purposes as observing barr bodies and chromosomes, and for culturing to produce cells of both epithelial and fibroblastic morphology. Three main hair categories are also described. (JN)

Describes the experimental procedures used for detecting DNA and RNA synthesis in xenopus cells by autoradiography. The method described is suitable for senior high school laboratory classes or biology projects, if supervised by a teacher qualified to handle radioisotopes. (JR)

Describes the experimental procedures for isolating fungi and demonstrating their tolerance of fungicides such as creosote and organic mercury. (JR)

Describes experiments using crude isolated chloroplast fractions which demonstrate some aspects of the photosynthetic light requiring process and a number of factors affecting them. These experiments are suitable for senior high school and college courses in biology. (JR)

Offers suggestions for teaching some aspects of water economy in plants. These include diffusion/osmosis, water transport, the part played by turgor in structural support, and its implications for plant organs or whole plants. Several practical demonstrations/experiments are also described. (JN)

Describes modifications of a Nuffield experiment demonstrating oxygen transport by blood since the current experiment more often than not produces unsatisfactory results. Includes experimental modification, instructional strategy, assembly of equipment, and a brief discussion. (JN)

Techniques for examining terrestrial and aquatic microorganisms using flattened glass capillaries are described. Capillaries can be left in natural or artificial environments for appropriate periods of time and removed for direct microscopic examination. Examples of organisms observed using the technique are given and suggestions made for wider…

Describes the life cycle, reproduction, and various classroom uses of the Louisiana Red Swamp Crayfish. Includes advantages and disadvantages of two different culturing techniques. (JN)

Presented is a cytogenic technique which enables students to produce preparations of dividing cells. Described are materials, methods, typical results, and assessment for this activity. The usefulness for a wide range of ages and abilities is stressed. (CW)

Described is a simple technique to monitor air pollutants and to simulate some of the features of roadside canopies. Included are the procedures, directions for the assembly of the apparatus, and a discussion of typical results. Graphs of sample data are presented. (CW)