The effects of impeller size, agitation and aeration on the rate of yeast growth were investigated using bench-top bioreactors. This exercise, carried out over a six-month period, served as an effective demonstration of the importance of different operating parameters on cell growth and provided a means of determining the optimisation conditions…

Leaves of higher terrestrial plants have small pores--stomata--responsible for gas exchange. The opening of each stoma results from the osmotic uptake of water by two specialised cells--the guard cells. Because of the involvement in this mechanism of ATPase-proton pumps and active transport of ions across membranes, we have designed an Exploring…

Fully opened leaves of potted plants of "Oxalis corymbosa" DC. closed completely by folding their leaflets downward after being kept in the dark for two hours. The folded leaflets, then moved upward gradually after exposure to light. We developed a simple method to measure the leaf movement. A paper protractor folded every 10[degrees] was devised…

In this article the effect of light quality on the size of the photosystem II (PSII) light harvesting complex (LHCII) is studied by measuring the chlorophyll fluorescence emitted by leaf sections of oat ("Avena sativa," var. Prevision) plants previously treated with either white light or with light filtered through blue, green, red or farred…

Three experiments show latent (or incidental) learning of salt-cue relationships using a conditioned cue-preference paradigm. Rats drank a salt solution while confined in one compartment and water in an adjacent, distinct compartment on alternate days. When given access to the two compartments with no solutions present, sodium-deprived rats…

Although the theory of evolution is the foundation of modern biology, students too rarely have an opportunity to watch selection operate in natural populations of animals. This lack may be partially responsible for the unfortunate ignorance of many people regarding the significance of evolution in biology. Laboratory exercises that directly study…

The Environmental Inquiry program supports inquiry based, student-centered science teaching on selected topics in the environmental sciences. Many teachers are unfamiliar with both the underlying science of toxicology, and the process and importance of peer review in scientific method. The protocol and peer review process was tested with college…

It seems hard to believe that Dolly the cloned sheep was born 10 years ago, kindling furious arguments over the prospects and ethics of cloning a human. Today, the controversy over cloning is entwined, often confused, with concerns over the use of human embryonic stem cells. Most people are unclear what cloning is, and they know even less when it…

The purpose of this guide is to highlight some broad areas in which teachers and other adults have exceptional opportunities to encourage and enjoy teaching children science. Each area in the book provides some hands-on ideas for projects as well as an annotated list of readily available resources that might prove helpful on the topic at hand. The…

This book contains innovative hands-on science laboratory activities that teach basic scientific method skills and are designed to be used directly with 4th- through 9th-grade students. The background materials and instructions included in each activity are written for students to work together in teams. Lab titles are: observation lab,…

This paper describes the first phase of a study to investigate students' evaluations of computer laboratory modules in a university-level, non-majors biology course. The National Science Foundation-funded project has two primary goals: (1) to develop programmable, multifunctional Bio LabStations for data collection and analysis, lab extensions,…

This book is provided as a helpful tool in ensuring a successful and satisfying elementary school science fair. The book clarifies the roles of teachers, parents, and students and provides information about types of projects, practical tips, and possible topics for research. Included are short bibliographies, sample forms (which are teacher…

This collection of lesson plans designed for teachers of 4th- through 12th-grade students utilizes an assortment of teaching strategies for topics related to coal and the coal industry. Activities cover the following topics: coal formation; coal identification; "the geologist's dilemma" (a supply and demand activity); geologic time and…

Distillation in the chemistry laboratory is an essential part of a practicing chemists' and a chemistry educators' work. Nevertheless, regardless of the degree of importance in each of the aforementioned professions, few educational studies on teaching and learning distillation exist. In an effort to rectify this oversight, the Department of…

This document describes ways to work with DNA and host organisms in precollege classrooms. The guidelines are intended to assist the teacher who already has training in working with microbes, DNA, and associated chemicals. The contents of the guidelines include: (1) Permitted DNA molecules, vectors, and recommended host organisms for constructing…