Select the correct description regarding the chemical messengers released by glands found on top of kidney.

Options

A. Aldosterone stimulates the reabsorption of `K^+` and water from the renal tubules.
B. Cortisol is a major glucocorticoid.
C. Glucocorticoids promote cellular uptake and utilisation of amino acids.
D. Androgens helps in the maintenance of body fluid volume and osmotic pressure only.

Answer

To solve the question regarding the chemical messengers released by the glands found on top of the kidneys, we need to analyze the statements provided about the hormones produced by the adrenal glands. Here’s a step-by-step breakdown:

### Step 1: Identify the Glands
The glands located on top of the kidneys are called the adrenal glands. They produce several important hormones.

**Hint:** Remember that the adrenal glands are responsible for producing hormones that help regulate metabolism, immune response, and stress.

### Step 2: Analyze the First Statement
The first statement claims that "Aldosterone stimulates the reabsorption of potassium from the renal tubule." This statement is incorrect. Aldosterone actually stimulates the reabsorption of sodium and water, while promoting the excretion of potassium.

**Hint:** Focus on the primary function of aldosterone, which is related to sodium and potassium balance.

### Step 3: Analyze the Second Statement
The second statement asserts that "Cortisol is a major glucocorticoid." This statement is correct. Cortisol is indeed the primary glucocorticoid produced by the adrenal cortex and is often referred to as the "stress hormone."

**Hint:** Recall the role of cortisol in the body, especially in response to stress.

### Step 4: Analyze the Third Statement
The third statement suggests that "Glucocorticoids promote cellular uptake and utilization of amino acids." This statement is incorrect. Glucocorticoids actually inhibit the uptake and utilization of amino acids and stimulate gluconeogenesis, lipolysis, and proteolysis.

**Hint:** Think about how glucocorticoids affect metabolism, particularly in stressful situations.

### Step 5: Analyze the Fourth Statement
The fourth statement claims that "Androgens help in the maintenance of body fluid volume and osmotic pressure only." This statement is also incorrect. While androgens do play a role in fluid balance, it is primarily aldosterone that is responsible for maintaining body fluid volume and osmotic pressure.

**Hint:** Differentiate between the roles of androgens and aldosterone in the body.

### Conclusion
After analyzing all the statements, the only correct statement is the second one regarding cortisol being a major glucocorticoid. Therefore, the correct answer is the second option.

**Final Answer:** The correct description is that "Cortisol is a major glucocorticoid."