If your patient has a higher than normal pH (alkalosis), you would expect to also see:

Choice A reason: This is incorrect because intracellular fluid is greater than extracellular fluid in a hypertonic state, not an isotonic state. A hypertonic state is when the solute concentration of the extracellular fluid is higher than the intracellular fluid, which causes water to move out of the cells and shrink them.

Choice B reason: This is incorrect because extracellular fluid is less than intracellular fluid in a hypotonic state, not an isotonic state. A hypotonic state is when the solute concentration of the extracellular fluid is lower than the intracellular fluid, which causes water to move into the cells and swell them.

Choice C reason: This is correct because intracellular and extracellular fluid is equal in an isotonic state. An isotonic state is when the solute concentration of the extracellular fluid is the same as the intracellular fluid, which causes no net movement of water across the cell membrane.

Choice D reason: This is incorrect because interstitial fluid is less than the transcellular fluid in a situation of fluid imbalance, not an isotonic state. Interstitial fluid is the fluid that surrounds the cells, while transcellular fluid is the fluid that is contained in specialized cavities, such as cerebrospinal fluid, synovial fluid, or pleural fluid. The amount of transcellular fluid is normally very small compared to the interstitial fluid, but it can increase in certain conditions, such as edema, ascites, or hydrocephalus.

Choice A reason: This is incorrect because the adrenal gland is not involved in the thirst mechanism. The adrenal gland is responsible for producing hormones such as cortisol, aldosterone, and adrenaline, which regulate stress response, blood pressure, and metabolism.

Choice B reason: This is incorrect because the cerebral cortex is not involved in the thirst mechanism. The cerebral cortex is the outer layer of the brain that is responsible for higher cognitive functions such as memory, language, and reasoning.

Choice C reason: This is incorrect because the pituitary gland is not directly involved in the thirst mechanism. The pituitary gland is a small gland at the base of the brain that produces hormones that control growth, reproduction, and metabolism. However, the pituitary gland does secrete antidiuretic hormone (ADH), which is regulated by the hypothalamus and affects water balance in the body.

Choice D reason: This is correct because the hypothalamus is the location of the thirst mechanism. The hypothalamus is a part of the brain that regulates many bodily functions such as temperature, appetite, sleep, and emotions. The hypothalamus also monitors the blood osmolarity and triggers the sensation of thirst when the blood is too concentrated.