Word: pupa
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Chemist Clever soon had his answer. Within 20 minutes after a larva got an injection of ecdysone, its chromosomes grew puffs. Shortly after that, the larva turned into a pupa...
...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...
...winner of the 1939 Nobel Prize in Chemistry (for isolating the male sex hormone, androsterone), a research team at Munich's Max Planck Institute for Biochemistry imported 1,000,000 silkworm cocoons from Italy and Japan, opened them up with razor blades, separated the pupae of 310,000 females from the males. What followed, in the words of one researcher, was "a mass slaughter, and not for the fainthearted." Each tiny pupa was disemboweled, the scent glands carefully cut out. Male moths served as lab assistants: when they were placed near fractions into which the gland material had been...
Biologists guessed a generation ago that the metamorphosis of insects (changing from larvae to pupae and from pupae to adults) is probably controlled by a chemical hormone. Three years ago Dr. Williams extracted an oil from the abdomens of silkworm moths, injected it into silkworm pupae. It stopped their normal development. The pupae never became adult moths, instead developed into a second kind of pupa. Smaller doses brought forth monstrosities with mingled patches of adult and juvenile tissue. Williams concluded that the oil contained a "juvenile hormone...
...this experience, both males and females are sterile but otherwise undamaged. When they emerge from the pupa cases two days later as vigorous adults, they are packed into small cartons, loaded into airplanes for release over Florida and parts of adjacent states...