An increase in capillary blood pressure would tend to:

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: 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.

Correct Answer: C

Rationale: In dehydration, the body first draws fluid from the interstitial space to maintain blood volume, leading to a decrease in interstitial fluid volume. This is why choice C is correct. Choice A is incorrect because intracellular fluid is not the first to be affected. Choice B is also incorrect as plasma volume reduction typically occurs after interstitial fluid loss. Choice D is incorrect as dehydration impacts both interstitial and intracellular fluid volumes.

Correct Answer: D

Rationale: Dehydration can result from significant fluid loss due to vomiting, diarrhea, or inadequate fluid intake. Prolonged vomiting and diarrhea lead to excessive fluid loss from the body, contributing to dehydration. Similarly, not consuming enough fluids can also result in dehydration. Choice A and B are too specific as they only mention one cause each, while choice C is also correct but does not encompass all the potential causes of dehydration as mentioned in choice D.