Page 12 - The Cell in 40 Topics

he level of water within the human body is of the greatest im-
portance, because if it falls below a certain level or accumulates
to excess, that life-giving water can give rise to possibly fatal re-
sults. Do you know what the ideal amount of water in your body is?
Moreover, are you able to determine the amount of water your body con-
tains and take steps to maintain that ideal level? Of course not! Until you
read this page, you may never even have considered that question. That is
because your body contains an extraordinary self-governing system that
flawlessly performs this important duty for you. The details of this system
contain a number of astonishing miracles. Let us now examine it in some
detail:
In the membranes of hypothalamus cells in the brain, there are recep-
tors whose job is to measure the fluid level in the blood. Notice that it isn't
a laboratory staff or trained doctors who determine the level of fluid in the
circulatory system, but minute receptors in the delicate membranes of cells
that are themselves too small to be perceived with the naked eye.
In order to comprehend the scale of the information, ability and tech-
nical prowess that this vital function requires, we can use a comparison: No

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