Word: gland
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Dates: during 1940-1949
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Most scientists use jawbreaking words for relatively simple things. A biologist says he has "hypophysectomized" a pigeon when he has removed its pituitary* gland; a psychologist speaks of "tactual-kinesthetic perception" when a blindfolded person indicates a point on his skin which has been stimulated. The opposite is true in mathematics, where ordinary words have fearfully complex meanings-e.g., "fields," "groups," "families," "spaces," "rings," "limits," "domains," "functions." In mathematics, a "simple curve" is a closed curve, no matter how elaborate, which does not cross itself-that is, which has one inside and one outside (see cut). An ordinary figure...
...creatures secrete an easily oxidizable compound, luciferin, which is oxidized with the help of an enzyme, luciferase. The exact chemical nature of luciferin and luciferase varies from species to species-firefly luciferin, for example, is no good when mixed with luciferase from worms. The reaction may occur in special gland cells, or the animal may eject luminous material. Some deep-sea squid throw off luminous puffs to confuse attackers, but this dodge is not always effective...
When the delicate artery branches, or arterioles, tighten and dam up the flow of blood in the main arteries, this pressure is greatly increased. Some causes of hypertension : overactivity of the thyroid gland, emotional disturbances, an abnormally large volume of circulating blood, toxemias of pregnancy. Normal blood pressure increases with age, ranges from no to 135 for a normal adult male.* High blood pressure may climb...
Biologists Edwin Eustace Reinke and Claude Simpson Chadwick of Vanderbilt University and the Highlands (N.C.) Biological Laboratory nabbed some North Carolina specimens of T. viridescens in the immature red eft stage and implanted bits of adult pituitary gland in their muscles. Within six days the newts went into the water and assumed the adult body color and tail shape. Thus it seemed that the pituitary provided not only the necessary physiological changes for aquatic life but also the "water drive" or impulse to seek water...
...mammals the pituitary, that master gland, secretes a half-dozen or so hormones (no one knows exactly how many) which control or influence growth, body heat, blood pressure, milk production, maternal behavior, etc. Sometimes the pituitary achieves its ends by stimulating other glands, such as the sex glands or thyroids, to produce hormones of their...