Considers current knowledge of the evolutionary origin, the development of the structure, the composition, and the morphogenetic regulation of chloroplasts. (AL)

Describes plant tissues that naturally contain substances poisonous to human beings if taken in large amounts. Some of these toxic materials are found in vegetables and fruits, as well as plants we normally don't eat such as yew. Also notes that plants recently sprayed with pesticides are harmful. (BR)

Presents detailed instructions for creating and using natural fabric dyes extracted from plants, a project which the authors have used with first- through sixth-graders. (SJL)

A comprehensive discussion of the biological activity in tidal pools is provided. The importance of environmental factors such as oxygen supply, temperature, salinity, and light is detailed. Plants and animals that might be found in a tidal pool are identified and described. (BT)

Presents a number of simple exercises that demonstrate potato tuber characteristics and are designed for high school biology students and teachers. Exercises include Typing, Grading, Shape, Eye Characteristics, Defects, Specific Gravity, Dry Matter Content, Glucose Content, Baking, Frying/Chipping, and Taste Testing. (JRH)

Highlights glucosinolates-a family of secondary metabolites from plants of high culinary and nutritional value. Describes experiments that demonstrate the enzymatic degradation of glucosinolates. Teaches students about the distribution, variation, chemistry, and function of a family of natural products important in plant protection, food spicing,…

Introduces sequoias, the largest tree species, and describes the importance of fires in sequoias' successful reproduction and management of the sequoia ecosystem. (Contains 23 references.) (YDS)

Presents an experiment that challenges the claim that sprouting radish seedlings release chemicals into the environment that inhibit germination of lettuce seeds. Reports that although no simple allelopathic demonstration was observed, the experiment provides fertile ground for further experimentation in inquiry-based laboratory experiences. (JRH)

Presents an activity that involves using sponge seedlings to demonstrate the germination process without the usual waiting period. Discusses epigeous versus hypogeous germination, and cotyledon number and biodiversity. (JRH)

Researchers who study the fossil record are seeking to determine whether the impact made by a comet or meteor really did decimate up to half of the life on this planet at the end of the Cretaceous period. Questions whether the extinction of plant and animal life was abrupt, started before the impact, or was a gradual change. (KR)

Reviews new developments in biotechnology--designer enzymes, biomining, gene cloning. Includes student outcomes, quiz, glossary, and a design brief on genetics. (SK)

Describes how a classroom observation of apples led to the development of a science project. Discusses the correlation between the greenness and the acidity of apples. Finds that the greener the apple, the lower its pH, and thus the more acidic and less sweet it tastes. (Author/CCM)

Describes The Habitat Puzzler, an activity that bridges the gap between education and entertainment. Illustrates the concepts of native plants and wildlife through five interpretive stations. (CCM)

Discusses the increasing interest of the public in nature and art of the 18th and 19th centuries, and making watercolor painting a part of the curriculum. Focuses on the works and publishing of Gwillim, Wilson, Audubon, and Peterson. (Contains 12 references.) (YDS)