Word: eggs
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Dates: during 1950-1959
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...sexual reproduction, the chromosomes behave differently. The sex cells (sperm and egg) are the end results of a complicated process (meiosis or reduction division) that gives each of them half as many chromosomes as in the nonsexual cells. This reduction is necessary because the sex cells join during fertilization of the egg, and if each contributed a full set of chromosomes, the fertilized egg would have twice the normal number. But if both sperm and egg contribute half as many chromosomes, the fertilized egg gets just the right number...
Many years before the birth of the science of genetics, the chromosomes had been observed behaving in this way, but no one knew why they did. Genetics supplied the answer. Reduction division is a kind of lottery that deals the fertilized egg half a set of chromosomes from each parent, like cards dealt out to players in a two-handed card game. When maternal and paternal chromosomes are slightly different, which is generally the case, their dominant genes (units of heredity) suppress recessive genes, as Mendel's red-flowered peas suppressed white-floweredness. Each recessive gene is still riding...
...some mysterious way absorbs them selectively through its outer wall. Tiny, mysterious bodies move through its protoplasm, and inside the nucleus reside the powerful chromosomes, which most geneticists believe are like a chemical oligarchy controlling the activities of a chemical nation. If the cell is a fertilized egg, the chromosomes possess all the information needed to build the cell into a bug or a whale...
Here, the geneticists now believe, lies the high command of growth and reproduction. Double-helix DNA molecules, thousands of turns long and arranged by thousands in each chromosome, can carry a vast amount of coded information. They may very likely carry enough to determine whether a fertilized egg grows into a clam or an elephant. When chromosomes replicate during cell division, the DNA molecules that they contain presumably replicate...
...figure of a gaunt man with porthole-sized gaps in his anatomy, holding a staff topped with a mostly black butterfly. This, said Dali in an explanatory blurb, "portrays human anxiety." Next on the way "toward a harmonious tranquillity" came a diaphanous female figure with a winged-egg head, who carried a staff with a crepuscular moth. The third figure was what Dali called "the true butterfly of tranquillity"-a maiden in yellow, with a head composed of blue, red and yellow flowers. For a finale, there was another maiden (with real hair) skipping rope...