Which hormone reduces the amount of water in the body?

Correct Answer: B

Rationale: The correct answer is 'aldosterone.' Aldosterone is the hormone that reduces the amount of water in the body by increasing the reabsorption of sodium and water from the kidney tubules. ANH (atrial natriuretic hormone) actually works to increase the excretion of sodium and water by the kidneys, leading to a reduction in blood volume and pressure. ADH (antidiuretic hormone) works to increase water reabsorption by the kidneys, thereby increasing blood volume. Therefore, choices A (ADH) and D (ADH and aldosterone) are incorrect in the context of reducing the amount of water in the body.

Correct Answer: A

Rationale: An increase in capillary blood pressure leads to a higher force pushing fluid out of the capillaries into the interstitial space, thereby increasing interstitial fluid volume. Choice B is incorrect because capillary blood pressure affects the movement of fluid into the interstitial space, not into the plasma. Choice C is incorrect as an increase in capillary blood pressure would not decrease interstitial fluid volume. Choice D is incorrect as it combines contradictory effects when capillary blood pressure increases.

Correct Answer: D

Rationale: A decrease in blood protein concentration would lead to a reduction in osmotic pressure, which is responsible for drawing fluid back into the capillaries. This decrease in osmotic pressure would result in an increase in interstitial fluid volume as fluid moves out of the capillaries, and a decrease in blood plasma volume as less fluid is drawn back into the circulation. Therefore, the correct answer is to increase interstitial fluid volume and decrease blood plasma volume. Choices A, B, and C are incorrect because they do not reflect the impact of decreased blood protein concentration on fluid volumes.

Correct Answer: C

Rationale: The correct answer is C: Protein in the blood plasma. Plasma proteins, especially albumin, create oncotic pressure, which is the main force responsible for holding water within the blood capillaries. Capillary blood pressure (Choice A) is involved in pushing blood through the capillaries, while sodium and chloride in the blood plasma (Choices B and D) are electrolytes and do not play a significant role in the water-holding force within capillaries.

Correct Answer: A

Rationale: The correct answer is A, blood pressure. Blood pressure is the primary force that pushes fluid out of the capillaries into the surrounding tissues. This pressure difference is essential for the exchange of nutrients, gases, and waste products between the blood and tissues. Choices B, C, and D are incorrect as they do not represent the primary force responsible for pushing fluid in blood capillaries.