Word: cecropia
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...noise is not yet loud enough to disturb the sloths munching on the leaves of the cecropia trees, or the river terns that wing lazily over the Amazon's mighty waters, or the secretive Indian tribes that live deep within the jungle. But along the tributaries of the world's largest river the sound is plainly discernible, like a low rumble of thunder in the distance. It is the dull, grinding roar of bulldozers cutting naked red strips through the vast Amazon rain forest...
...current issue of Applied Optics, Entomologist Philip Callahan, of the Department of Agriculture, reports on delicate experiments with which he answered the question. Callahan caught some giant cecropia moths, which live in the woods, studied them under a binocular microscope and decided that it was tiny spikes at the base of their delicate, fernlike antennae that reacted to strong light. To check his theory, he blacked out the moths' eyes, painted each antenna black, except for the tips of the spikes, and ran minuscule wires into the main antennal nerves. Then he began subjecting them to light of varying...
...test this theory Pappenheimer needed an experimental animal in which the blocking of cytochrome synthesis would produce readily detectable effects. The Cecropia silk worm satisfied the requirement. During both the caterpillar phase and the period of adult development Cecropia produces substantial quantities of cytochromes. In the dormant pupa stage, though, the enzymes occur in only trace amounts. By showing that resistance to diphtheria toxin in the pupa stage is much greater than during other phases, Pappenheimer furnished compelling evidence for his theory...
Sleeping Pupa.The three "cytochrome" enzymes are basic growth factors. Present in human beings as well as in silkworms, they control the utilization of oxygen in the tissues. Without them growth is impossible. The dormant Cecropia pupa contains no cytochrome enzymes. Therefore it cannot grow until they are provided by the chain of hormones that starts in its brain...
...annual $1,000 prize of the American Association for the Advancement of Science went this year to Zoology Professor Carrol Milton Williams of Harvard. His research* on the hormone system that makes the native silkworm (Cecropia) turn into a moth had nothing to do with silk production; it was aimed at the central secrets of growth and life...