Word: insects
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...hormone is secreted by a pair of prothoracic glands in the body of the insect. In the vertebrate, this action seems, to be paralleled by the growth hormone secreted by the pituitary land...
Wakening Discs. When the caterpillar is full-sized, its tissues dissolve to form a yolky fluid. The imaginal discs wake up suddenly. Nourished by the fluid, they burst into furious growth, constructing within the larva's old skin an entirely new insect: the hibernating pupa. Later, a similar burst of growth turns the pupa into the adult moth...
Working with radioactive tracers and delicate chemical tests, Dr. Williams and colleagues followed the progress of this two-stage wave of growth. It starts, they found, in a tiny group of 22 cells in the insect's brain. These generate a hormone that acts upon glands in the body, making them produce another hormone. This in turn causes certain cells to produce three enzymes (organic catalysts) that start the rapid growth of metamorphosis...
...jury of scientists unanimously selected as "an outstanding contribution to science" the five papers published by the group on a hormone in the Cecropia silkworm which controls the insect's growth and mental functions...
Glands in the silkworm secrete the hormone which controls the production of an enzyme called cytohrome. This cytochrome is directly responsible for the growth and metamorphosis of the silkworm. Without it, the insect cannot change from caterpillar to pupa to moth. Such an enzyme in a human may be the cause of the malignant growths called cancers...