Final answer:
Drinking in response to osmotic or hypovolemic thirst is primarily controlled by osmoreceptors in the hypothalamus and the release of antidiuretic hormone (ADH), which regulates the concentration of solutes in the blood and helps to maintain proper hydration levels.
Step-by-step explanation:
Drinking in response to osmotic thirst or hypovolemic thirst appears to result from stimulation of the osmoreceptors and the release of antidiuretic hormone (ADH). Osmoreceptors, located in the thirst center of the hypothalamus, monitor the solute concentration of the blood and trigger a thirst response when blood osmolality rises. ADH, released by the posterior pituitary gland, directs the kidneys to conserve water and helps dilute the blood plasma. Additionally, the hypothalamus can influence the salivary glands to produce a sensation of dry mouth, encouraging the individual to drink water and rehydrate.
Alcohol consumption can cause increased urine output because it inhibits the release of ADH, leading to less water reabsorption in the kidneys and thus more dilute urine.