States the procedure for isolating actinomycetes from soil and testing for antibiotic growth. (LS)

Discusses the work of evolutionary biologists in determining how sexual reproduction arose. Topics explored include the nature of sex, bacterial sex, meiotic sex, and asexual reproduction. A diagram (which can be used as a duplicating master) illustrating types of bacterial sex is included. (DH)

Errors in determining the effectiveness of mouthwashes, disinfectants, and other household products as antibacterial agents may result from using broth cultures and/or irregularly shaped bits of filter paper. Presents procedures for a better technique and, for advanced students, two additional procedures for introducing quantitative analysis into…

Describes new methods of collecting and examining ciliates, particularly those found in the sediments of lakes, rivers, and estuaries. Discusses extraction methods in preparation for observations in the classroom. Suggests investigations of ciliate ecology as an area of increasing research interest. (JM)

The use of instant agar-free media in high school biology classes is discussed. The synthetic media are relatively inexpensive, heat stable, dependable, and time-saving. (Author/PEB)

Presented is a simulation program for Apple II computer which assays the effects of a series of variables on bacterial growth and interactions between microbial populations. Results of evaluation of the program with students are summarized. (CW)

This section of the journal includes several short notes on science activities and materials for secondary schools. Activities and materials are included that relate to biology, microbiology, microcomputers, chemistry, and physics. (RH)

Examines heterologous expression in Escherichia coli and the role of regulatory sequences which control gene expression at transcription resulting in abundant production of messenger RNA and regulatory sequences in mRNA which promote efficient translation. Also examines the role of E. coli cells in stabilizing mRNA and protein that is…

Provided are directions for culturing bacteria by using yoghurt as a culture medium. Yoghurt is a safe medium and results in an end product which may be eaten if desired. (PB)

Directions for the building of a pocket microscope that will make visible the details of insect structure and living bacteria are described. Background information on the history of microscopes and lenses is provided. The procedures for producing various types of lenses are included. (KR)

Explains some of the ways in which dried yeast has been used in sixth-form work to illustrate some points and principles relevant to a high school biology course. (Author/GA)

Methods are described for the induction and identification of respiratory deficient mutants in yeast. Practical schemes are given to enable students to obtain dose-response information for physical and chemical mutagens such as heat, ultraviolet light, or acriflavine. A simple test for environmental mutagens is described. (Author/MA)

Procedures are described for showing the effectiveness of antibiotics (penicillin, ampicillin, and tetracycline) against a nonpathogenic bacteria strain (Bacillus cereus). Methods are outlined for preparing nutrient agar, sterilizing tubes, pouring agar plates, preparing antibiotic discs, and transferring antibiotic discs to agar plates. (CS)