Browse Items (142 total)

Presents the case histories of three county-wide recreation programs as observed by an interested group. Outlines the various arrangements of financing a recreation program, shows the many reasons why trained leadership is necessary, discusses the…

Studies a green alga Volvox carteri f. nagariensis as a basis for understanding the growth and differentiation of other organisms. Focuses on the developmental stages of male, female, and asexual embryos. Separates gonidia from the parent spheroids…

Studies the early stages of the development of the axolotl, an aquatic salamander, with emphasis upon genetically determined characteristics. Mates two wild-type, dark axolotls, each heterozygous for white and albino mutations. Uses time-lapse…

Traces heart development in the early chick embryo, showing the primitive streak stage, heart-forming cells in the blastoderm, development and fusion of paired endocardial tubes and of the epimyocardium, gut closure, and later development of the…

Utilizes the living chick embryo and perspective drawings to show the early development of the amnion, chorion, yolk sac, and allantois. Examines the contractions of the amnion, as well as the folds and blood vessels of the yolk sac and its…

Shows the variety of ways animals obtain food and their different types of digestive cavities--fully closed, one opening, and two openings. Examines digestive organs in an earthworm, grasshopper, frog, cat, and bird. Looks at peristalsis in a dog's…

A dramatization which compares responsible drinking with alcohol abuse. Intermixed with scenes from a party, a male and female participant each present facts about alcohol consumption and its effect on physical and mental functioning. Contrasts the…

Describes the nature and characteristics of minerals and rocks and the importance of these attributes for identification and classification. Uses time-lapse photography to show growing crystals and to depict the way crystals form minerals in the…

Examines the evidence concerning the origin and development of living forms, providing a general framework for fossil study and for the appreciation of earth history and paleontology as fields of investigation. Drawing on specimens, reconstructions,…

Shows the methods scientists use to obtain knowledge about the earth's interior and explains that this information is limited because the interior cannot be directly observed. Observes seismic, gravitational, magnetic, and thermal observations which…