Excess or lack of water is detected by the hypothalamus in the brain, it causes the pituitary gland to produce Anti-diuretic hormone, or ADH. This hormone then travels through the blood stream to the kidneys, when it reaches them the kidneys lower the amount of water that is excreted by the body, and increase the amount of water that is reabsorbed into the blood stream. The urine is then more concentrated with a lower volume.
If there is too much water the levels of ADH are lowered and the opposite effects happen, resulting with a more dilute urine and less water in the blood.
ADH makes the collecting duct become more permeable meaning more water is reabsorbed
ReplyDeleteCorrect!
DeleteBlood too concentrated --> detected by hypothalamus --> pituitary gland releases more ADH --> makes collecting duct more permeable to water --> more water reabsorbed --> urine more concentrated.
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