The inability to regulate the concentration of sodium ions in the blood could be due to the improper functioning of one of the following

Options

A. Pars nervosa : It produces ADH
B. Adenohypophysis : It produces TSH
C. Adrenal cortex - It produces aldosterone
D. Adrenal medulla : It produces epinephrine

Answer

To solve the question regarding the inability to regulate the concentration of sodium ions in the blood, we need to identify which endocrine gland is responsible for this regulation. Here’s a step-by-step solution:

### Step 1: Identify the glands and their functions
We are given four options related to different endocrine glands. We need to understand the primary functions of each gland mentioned.

1. **Pars Nervosa (Posterior Pituitary)**: This part of the pituitary gland releases Antidiuretic Hormone (ADH), which primarily helps in the reabsorption of water in the kidneys.

2. **Adenohypophysis (Anterior Pituitary)**: This part of the pituitary gland produces Thyroid Stimulating Hormone (TSH), which stimulates the thyroid gland and regulates metabolism but does not directly regulate sodium levels.

3. **Adrenal Cortex**: This gland produces aldosterone, which is crucial for the reabsorption of sodium ions in the kidneys.

4. **Adrenal Medulla**: This part of the adrenal gland produces epinephrine (adrenaline), which is involved in the body's stress response and does not regulate sodium levels.

### Step 2: Determine the gland responsible for sodium regulation
From the functions identified, we can see that the **Adrenal Cortex** is responsible for producing **aldosterone**, which directly regulates the concentration of sodium ions in the blood by promoting their reabsorption in the kidneys.

### Step 3: Conclusion
Therefore, if there is an inability to regulate sodium ion concentration in the blood, it could be due to the improper functioning of the **Adrenal Cortex**.

### Final Answer:
The inability to regulate the concentration of sodium ions in the blood could be due to the improper functioning of the **Adrenal Cortex**.

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