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: 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: B

Rationale: Chloride (Cl-) is the most abundant anion in blood plasma. It plays a crucial role in maintaining osmotic balance and acid-base homeostasis. Bicarbonate (Choice A) is important for buffering acids in the body but is not the most abundant negative ion in blood plasma. Hydroxide (Choice C) is not typically found in high concentrations in blood plasma. Phosphate (Choice D) is an important anion in the body but is not as abundant as chloride in blood plasma.

Correct Answer: B

Rationale: The correct answer is B, Interstitial fluid. Interstitial fluid is the fluid that surrounds and occupies the spaces between cells, providing them with nutrients and removing waste. Choices A, C, and D are incorrect because intracellular fluid refers to fluid inside cells, plasma refers to the liquid component of blood, and electrolyte refers to substances that dissociate into ions in solution, affecting fluid balance but not specifically found in spaces between cells.

Correct Answer: B

Rationale: When selecting a site for IV insertion on the hand or arm, it is important to consider the potential effects on the patient's mobility. The chosen site should not interfere with the patient's movement. Instructing the patient to hold his arm in a dependent position helps increase blood flow, aiding in vein visualization and insertion. It is advisable to choose a site with minimal hair if possible for better adhesion of the dressing. Removing the tourniquet after 2 minutes is recommended to prevent complications like hemoconcentration and potential vein damage. Therefore, option B is the correct choice as it aligns with best practices for IV insertion.

Correct Answer: C

Rationale: The correct answer is C: Sodium. Sodium (Na+) is the most abundant cation in the extracellular fluid, including blood plasma. It plays a crucial role in maintaining fluid balance, nerve function, and is essential for various physiological processes. Choice A, Potassium, is also an important ion in the body but is predominantly found intracellularly. Choice B, Calcium, is an essential mineral in the body but is not the most abundant positive ion in blood plasma. Choice D is incorrect as sodium is the primary positive ion in blood plasma, with a much higher concentration compared to potassium.

Correct Answer: A

Rationale: The correct answer is A: Skin. After the kidneys, the skin is the second largest route of water loss through perspiration. Choice B, Lungs, is incorrect as the lungs primarily exchange gases and do not play a significant role in water loss. Choice C, Intestines, is also incorrect as water loss through the intestines is minimal since most water is reabsorbed during digestion. Choice D, Muscles, is incorrect as muscles are not a major source of water loss in the body.

Correct Answer: A

Rationale: The correct answer is the kidneys. The kidneys are primarily responsible for regulating fluid balance by filtering blood and adjusting the volume and concentration of urine. The lungs primarily regulate gas exchange, not fluid balance. The skin plays a role in temperature regulation and protection but is not the primary organ for fluid output. The intestines are mainly involved in the absorption of nutrients and water, rather than fluid output.

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.