Which of the following statements is correct in relation to the endocrine system.

Options

A. Non - nutrient chemicals produced by the body in trace amount that act as intercellular messenger are known as hormones.
B. Releasing and inhibitory hormones are produced by the pituitary gland.
C. Adenohypophysis is under direct neural regulation of the hypothalamus.
D. Organs in the body like gastrointestinal tract, heart, kidney and liver do not produce any hormone.

Answer

To determine which statement is correct in relation to the endocrine system, we will analyze each statement provided in the question.

### Step-by-Step Solution:

1. **Analyze the First Statement:**
- The statement claims that non-nutrient chemicals produced by the body in trace amounts that act as intercellular messengers are known as hormones.
- **Evaluation:**
- Hormones are indeed non-nutrient chemicals.
- They are produced in trace amounts.
- They function as intercellular messengers, influencing the activity of other cells.
- **Conclusion:** This statement is **correct**.

2. **Analyze the Second Statement:**
- This statement claims that releasing and inhibitory hormones are produced by the pituitary gland.
- **Evaluation:**
- Releasing and inhibitory hormones are actually produced by the hypothalamus, not the pituitary gland.
- The hypothalamus regulates the pituitary gland's hormone secretion.
- **Conclusion:** This statement is **incorrect**.

3. **Analyze the Third Statement:**
- The statement claims that adenohypophysis (anterior pituitary) is under direct neural regulation of the hypothalamus.
- **Evaluation:**
- The adenohypophysis is regulated by hormones from the hypothalamus, not directly by neural signals.
- The posterior pituitary (neurohypophysis) is under neural regulation.
- **Conclusion:** This statement is **incorrect**.

4. **Analyze the Fourth Statement:**
- This statement claims that organs in the body like the gastrointestinal tract, heart, kidney, and liver do not produce any hormones.
- **Evaluation:**
- This is false as many organs produce hormones. For example:
- The gastrointestinal tract produces gastrin, secretin, and cholecystokinin.
- The kidneys produce erythropoietin.
- The liver produces angiotensinogen and hepcidin.
- **Conclusion:** This statement is **incorrect**.

### Final Conclusion:
The only correct statement in relation to the endocrine system is the **first statement** regarding hormones being non-nutrient chemicals produced in trace amounts that act as intercellular messengers.

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