Avoiding Self-Pollination Self-pollination, transfer of pollen from the stamen of a flower to the pistil of the same flower, as distinguished from cross-pollination. A few kinds of flowers are self-pollinating; that is, they can be fertilized with their own pollen. In most cases, however, nature takes great care to prevent self-pollination. Cross-pollination usually produces more [...]

How Experimenters Developed Hybrid Corn In 1905 George H. Shull and Edward M. East began developing new kinds of corn by placing pollen from one desirable strain of corn onto the silks of another strain. The process produced cross-bred strains called hybrid corn. After World War I, Henry A. Wallace (who became secretary of agriculture [...]

DEFINITION:1 a) the branch of biology that deals with the relations between living organisms and their environment b) the complex of relations between a specific organism and its environment 2 Sociology the study of the relationship and adjustment of human groups to their geographical and social environments. 1869: Birth of ecology. Most people are unaware [...]

Competition in Communities Competition is a characteristic of all communities. Plant roots in dry range lands compete for water. The trees of a rain forest compete for light. Crops compete for both of these as well as for nutrients. Competition is usually keen in areas where one type of community seems to overlap another. For [...]

Cheetah DEFINITION: 1 any living organism, excluding plants and bacteria: most animals can move about independently and have specialized sense organs that enable them to react quickly to stimuli: animals do not have cell walls, nor do they make food by photosynthesis 2 any such organism other than a human being, esp. a mammal or, [...]

WATER CONSERVATION Polluted water in one part of the world affects water sources everywhere. This happens because water moves through what is called the hydro logic cycle. In the hydro logic cycle 1) water moves into the air and clouds as it evaporates from oceans, lakes, and rivers. 2) the winds that blow around the [...]