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The water balance of the body is the balance between water taken in, (mainly by drinking), and water expelled in urine. The control of the amount water in the blood is an example of homeostasis. Changes in the water levels are detected by osmoreceptors that are found in the hypothalamus. The control is mediated by a hormone called anti-diuretic hormone (ADH). This hormone is released from the pituitary gland.

Table 2, shows the events that would occur in the body in two situations. Assume, that for each case, all other conditions are the same and the subject is kept in a warm room.

Table 2 : Water balance
Water balance

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