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Homeostasis: About the level of urine passed from a human

A human drinks 1000 CM3 of distilled water and measures the amount of urine passed at 30 minute intervals. The subject passes 175CM3 at 30 mins, 325CM3 at 60 mins, and 225 CM3 at 90 mins. Why does the subject pass more urine at 60 mins than 90 mins???

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Before we look at your actual numbers, let's define some terms and just look at urine homeostasis. I do not know exactly which of these mechanisms you have been studying, so you will need to decide that.
<br>homeostasis - same state, or constant state. The body has many physiological control mechanisms to keep internal conditions (eg. water balance, body temperature, oxygen) within a narrow range of normal values.
<br>loop of Henle - portion of the nephron in the kidney where the balance between urea, salt, and water in urine and blood is controlled. This is the actual area of filtration, but its effectiveness is under the control of various hormones.
<br>absorption vs reabsorption - in the kidneys, absorption refers to substances moving from the blood TO the kidney. Reabsorption refers to substances moving FROM the kidney back to the blood.
<br>anti-diuretic hormone ...