18261. Day of the killer tornadoes (15:35)

Date:
1978
Summary:
Documents the series of 147 tornadoes which struck the South and Midwest sections of the United States in April 1974. Includes extensive footage of the tornadoes in Xenia and Cincinnati, Ohio and i...

18262. Meiosis (12:01)

Date:
1956
Summary:
Uses animation to show the mechanism of meiosis, the chromosome halving cell division preceding the formation of sperm and egg cells and forming the basis of genetics.

18263. The glass wall (30:53)

Date:
1959
Summary:
Dramatizes episodes in the lives of four people to show that they need help with a hearing problem. Urges those with a hearing loss to seek professional help and reviews the agencies of the commun...

18264. Tuberculosis (third edition) (10:34)

Date:
1955
Summary:
Discusses causes of the spread of tuberculosis in the United States and stresses the need for community action in combatting the disease. Dramatizes the case history of a young woman patient, showi...

18265. Genetic loads in Mendelian populations (28:43)

Date:
1959
Summary:
Portrays the frequency of mutants in the population gene pool as dependent upon their rate of origination and selection coefficient. Discusses the population fate of dominant lethals (retinoblasto...

18266. Development of Inherited Pattern, 3--Organ Formation (29:52)

Date:
1962
Main contributors:
Dr. Ray Koppelman, University of Chicago; American Institute of Biological Sciences
Summary:
The transmission of patterns –Mendelian inheritance, the chromosome theory, linkage and crossover; the gene; heredity and environment; development of the inherited patterns with emphasis on vertebr...

18267. Germfree animals in medical research (19:22)

Date:
1960
Summary:
**WARNING: CONTAINS GRAPHIC IMAGES OF LAB TEST ANIMALS** Illustrates the basic techniques of obtaining germfree environment, germfree animals, and methods of germfree miantenance. Demonstrates the...

18268. Three deep (07:01)

Date:
1951
Summary:
A group of fourth-grade children play Three Deep under their teacher's supervision. They demonstrate forming a double circle, running and chasing, and two variations of the original game.

18269. Essentials of good speech : loudness, 2 (13:11)

Date:
1974
Summary:
Presents a lesson at the "Imitation Stage" on loudness. Demonstrates how to help a pupil correctly imitate loud and soft vowels through the process of shaping only one ingredient at a time.

18270. The Stanford-Binet test (20:18)

Date:
unknown
Summary:
Explains and illustrates the use of the Stanford-Binet test in the context of a school guidance program; indicates its accuracy of measurement; and how the results may be properly used. Gives the a...