Word: paramecium
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Dates: during 1940-1949
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...paramecium is a minute one-celled animal which multiplies both non-sexually (by simple division) and by a kind of primitive pairing. Several years ago, Dr. Sonneborn discovered that special strains of paramecia give off a poison (paramecin) that kills normal paramecia. The "killers" differ from the "sensitives" in only one known respect: the amount of a substance called "kappa" which they contain...
...paramecium, to rate as a killer, has to contain at least 200 particles of kappa. If it has less, it is a sensitive, and can be destroyed by killers with plenty of kappa. Dr. Sonneborn discovered that sensitive paramecia can be turned into killers at will. He put sensitive paramecia into a solution of mashed killer paramecia. Half of the sensitives absorbed kappa particles, which turned them into killers. Their descendants were killers...
Died. Herbert Spencer Jennings, 79, famed zoologist and geneticist who spent years (at Johns Hopkins, and the University of California at Los Angeles) studying the lives & loves of the hairy, green, one-celled Paramecium bursaria, in search of clues to the mysteries of more complex animals; after long illness; in Santa Monica, Calif...
Genes Not All. This classical explanation of heredity, taught in every biology textbook, is not wholly satisfactory. Some cells, notably certain cancer cells in mice, seem to develop oddly, defying their hereditary genes. At Indiana University, Dr. Tracy M. Sonneborn found that the one-celled animal paramecium sometimes did this...
...Cancer's estimated annual worldwide toll: 1,000,000. *The paramecium, a slipper-shaped animalcule less than 1/125 of an inch long, comes in eight sexes, multiples by dividing itself in two, lives in lily ponds, goldfish bowls, is sometimes found in drinking water...