Final answer:
Increased blood osmolality triggers thirst and the release of antidiuretic hormone (ADH), which prompt fluid intake and water reabsorption in the kidneys, respectively, to normalize the osmolality.
Step-by-step explanation:
Increased blood osmolality triggers the sensation of thirst and the release of antidiuretic hormone (ADH) in an effort to make us consume more fluid. When the osmolality of the blood increases, it signals the hypothalamus to both induce the feeling of thirst, encouraging us to drink water, and signal the posterior pituitary gland to release ADH. ADH works on the kidneys to promote reabsorption of water, which dilutes the blood plasma, thus reducing the osmolality of the blood back towards normal levels.
The regulation of ADH and thirst mechanisms are crucial for maintaining the body's fluid balance. They act as a part of a negative feedback system, which involves monitoring the osmolarity of the blood and adjusting water intake and retention accordingly to maintain homeostasis. In addition, dry mouth and reduced urinary output also occur as a result of ADH release, which further encourages water consumption and the conservation of fluids within the body.