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The Epic Interactive Encyclopedia 1998
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Epic Interactive Encyclopedia, The - 1998 Edition (1998)(Epic Marketing).iso
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B
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Biofeedback
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INFOTEXT
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1992-09-03
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548b
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14 lines
Modification or control of a biological
system by its results or effects.
For example, a change in the position or
trophic level of one species affects all
levels above it. Many biological systems are
controlled by negative feedback. When enough
of the hormone thyroxine has been released
into the blood, the hormone adjusts its own
level by `switching off' the gland that
produces it. In ecology, as the numbers in a
species rise, the food supply available to
each individual is reduced. This acts to
reduce the population to a sustainable level.