Advances in the field of molecular biology, powered by a technological revolution, have increased dramatically over the past decades. Notable developments such as the cloning of adult sheep, the sequencing of the human genome, and the production of genetically modified organisms capture the attention of biologists, their students, and the general…

Heavy faculty teaching loads and limited funds biology teachers designed certain objectives in order to increase the understandability of the subject matter of the laboratory exercises they write. In relation to these objectives an old "cookbook" laboratory exercise on yeast fermentation is introduced which involve students asking questions,…

An experiment to prepare a deuterium labeled adduct of a Lewis acid and Lewis base, to use computational methods allowing students to visualize the LUMO of Lewis acids, the HOMO of Lewis bases and the molecular orbitals of the adduct that is formed is developed. This allows students to see the interplay between calculated and experimental results.

Redgram (Cajanus cajan L.) extracts have been analyzed for the protease inhibitors using a new, sensitive, simple, and rapid method for detection of electrophoretically separated protease inhibitors. The detection involves equilibrating the gel successively in the protease assay buffer and protease solution, rinsing the gel in assay buffer, and…

The construction and use of a low-cost continuous-flow instrument for measuring the kinetics of fast reaction which include the use of an light emitting diode light source, a photodiode-on-a-chip detector, and a position sensor is demonstrated. The instrument is suitable for the physical chemistry laboratory and could be used to study the kinetics…

A simple, low-cost experiment to demonstrate the wetting dynamics of liquids on solid surfaces is described, where a "Web cam" is used to measure the expansion of the drop as a function of time. The advantage of a Web cam is its low cost, which permits an individual setup per student and the results obtained from the students with these devices…

Synthetic sequences in the undergraduate organic chemistry laboratory illustrate important synthetic strategies, reagents, or experimental techniques, oftentimes resulting in the synthesis of commercially important compounds. A fragrance with a 'spicy, carnation, sweet, vanilla', named after carnations (Dianthus caryophllus), Methyl Diantillis is…

A discovery-oriented lab experiment is developed that illustrates the chemoselective nature of reductions using sodium borohydride. Products are of sufficient purity to allow analysis by spectroscopy without further purification.

A lab rotary experiment using the pH measurements of an aqueous solution to monitor the course of a solvolytic reaction was conducted. This experiment allowed the students to gain experience in taking precise pH measurement, to use nonlinear analysis techniques for analyzing kinetic data and to use the Arrhenius equation for determination of…

Problems in the experimental laboratory in scientific research are discussed and solutions are proposed for the problem of conflicts between the experimental model and reality. As a possible beginning for change, an apparatus is suggested to replace the tachistoscope. (SCC)

Describes an experiment which measures the surface tension of a liquid and illustrates interfacial spreading and the Marangoni effect. (MLH)

Stefan's law is demonstrated by measuring the temperature of the tungsten filament of an electric light bulb and plotting a log-log graph of temperature against power dissipation. (MLH)

Presents experiments, demonstrations, activities and ideas relating to various fields of biology to be used in biology courses in secondary schools. Among those experiments presented are demonstrating the early stages of ferns and mosses and simple culture methods for fern prothalli. (HM)

Two experiments are presented which help to illustrate a modular approach to electrochemical instrument design, but which are readily understandable to students with a limited electronics background. The experiments are coulometric titration and controlled potential coulometry.

Describes a laboratory experiment demonstrating the aldehyde oxidase activity in wild type and mutant fruit flies using a quantitative assay. The experiment can be performed in one hour. (MA)