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: C

Rationale: The correct answer is C: Dehydration. Prolonged vomiting or diarrhea can lead to significant fluid loss, causing dehydration. Intracellular fluid (choice A) and interstitial fluid (choice B) refer to specific compartments of body fluid and are not conditions resulting from vomiting or diarrhea. Electrolytes (choice D) are minerals that help maintain fluid balance in the body but are not the condition directly resulting from prolonged vomiting or diarrhea.

Correct Answer: C

Rationale: The correct answer is C. Overhydration can occur when intravenous fluids are administered too quickly, overwhelming the body's ability to excrete the excess fluid. Choices A, B, and D are incorrect. Choice A is incorrect because overhydration is less common than dehydration. Choice B is incorrect because while overhydration can strain the kidneys, it is not due to the burden being too heavy. Choice D is incorrect because dehydration is more common than overhydration.

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: The correct answer is B: Respiratory alkalosis. Hyperventilation, which can be caused by extreme anxiety, is the most common cause of acute respiratory alkalosis. This leads to a decrease in PaCO2 levels. Respiratory acidosis, choice A, occurs in conditions like hypoventilation, leading to an increase in PaCO2 levels. Choice C, Increased PaCO2, is not the correct term for an acid-base imbalance related to hyperventilation. Choice D, CNS disturbances, is not directly related to the acid-base imbalance caused by hyperventilation.

Correct Answer: B

Rationale: Iodine is the correct answer because it is essential for the synthesis of thyroid hormones. The thyroid gland incorporates iodine into thyroid hormones such as thyroxine (T4) and triiodothyronine (T3). These hormones are crucial for regulating metabolism, growth, and development. Sodium, iron, and chloride are not directly involved in the formation of thyroid hormones, making them incorrect choices.

Correct Answer: B

Rationale: The correct answer is 'Intracellular fluid.' Intracellular fluid refers to the fluid contained within the cells, constituting a significant portion of the body's total water content. Choices A, C, and D are incorrect. Plasma is the liquid component of blood outside the cells, interstitial fluid is the fluid surrounding cells in tissues, and the combination of plasma and intracellular fluid is not the specific term for the fluid inside the cell.

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: D

Rationale: The correct answer is D. All the listed organs (lungs, skin, and intestines) contribute to fluid loss from the body. Lungs contribute to fluid loss through respiration, skin through sweating, and intestines through excretion. Therefore, none of the organs listed in the options retain fluids within the body. Choices A, B, and C are incorrect because all of these organs play a role in fluid output from the body.