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Aristotle (384–322 BC) studied at Plato's Academy in Athens, remaining there for about 20 years.Like Plato, he sought universals in his philosophy, but unlike Plato he backed up his views with detailed and systematic observation, notably of the natural history of the island of Lesbos, where he spent about two years, and the marine life in the seas around it, especially of the Pyrrha lagoon ...
Barbara McClintock breeds maize plants for color, which leads to the discovery of transposable elements or jumping genes (1944). Linus Pauling and colleagues show in "Sickle Cell Anemia, a Molecular Disease" that a human genetic disease, sickle cell anemia, is caused by a molecular change in a specific protein, hemoglobin (1949).
This resembled a large-scale pulse-chase experiment, but could not have been performed as a regular experiment in humans due to scientific ethics. Several types of observations were made possible (in people born before 1963), such as determination of the rate of replacement for cells in different human tissues.
Starch is stored in the amyloplasts, a specialized organelle found within plant cells, as starch grains. [4] The starch grain is specifically important for study due to the fact that it is commonly found in most plants, its long-lasting nature, as well as the diverse forms and structures that they can take based on which taxa they belong to.
Structure of a plant cell. Plant cells are the cells present in green plants, photosynthetic eukaryotes of the kingdom Plantae.Their distinctive features include primary cell walls containing cellulose, hemicelluloses and pectin, the presence of plastids with the capability to perform photosynthesis and store starch, a large vacuole that regulates turgor pressure, the absence of flagella or ...
Unwittingly, humans have carried out evolution experiments for as long as they have been domesticating plants and animals. Selective breeding of plants and animals has led to varieties that differ dramatically from their original wild-type ancestors. Examples are the cabbage varieties, maize, or the large number of different dog breeds.
Important general biological observations were made by Robert Hooke (1635–1703) but the foundations of plant anatomy were laid by Italian Marcello Malpighi (1628–1694) of the University of Bologna in his Anatome Plantarum (1675) and Royal Society Englishman Nehemiah Grew (1628–1711) in his The Anatomy of Plants Begun (1671) and Anatomy of ...
Micrographia: or Some Physiological Descriptions of Minute Bodies Made by Magnifying Glasses. With Observations and Inquiries Thereupon is a historically significant book by Robert Hooke about his observations through various lenses. It was the first book to include illustrations of insects and plants as seen through microscopes.