Which of the following hormones of the human body are not secreted by an endocrine gland?

Options

A. Parathyroid hormone
B. Growth hormone
C. ANF
D. Thyroxine

Answer

To solve the question regarding which hormone is not secreted by an endocrine gland, we will analyze each option provided in the question step by step.

### Step-by-Step Solution:

1. **Understanding Endocrine Glands**:
- Endocrine glands are ductless glands that secrete hormones directly into the bloodstream. Examples include the pituitary gland, thyroid gland, and parathyroid glands.

2. **Analyzing Each Hormone**:
- **Parathyroid Hormone (PTH)**:
- This hormone is secreted by the parathyroid glands, which are endocrine glands. Therefore, PTH is secreted by an endocrine gland.

- **Growth Hormone (GH)**:
- GH is secreted by the anterior pituitary gland, which is also an endocrine gland. Hence, GH is secreted by an endocrine gland.

- **Atrial Natriuretic Factor (ANF)**:
- ANF is secreted by the heart (specifically the atria). It is released into the bloodstream but is not produced by a traditional endocrine gland. Instead, it is released from the heart and acts on the kidneys. Thus, ANF is not secreted by an endocrine gland.

- **Thyroxine (T4)**:
- Thyroxine is produced by the thyroid gland, which is an endocrine gland. Therefore, T4 is secreted by an endocrine gland.

3. **Conclusion**:
- Among the hormones listed, the only one that is not secreted by an endocrine gland is **Atrial Natriuretic Factor (ANF)**.

### Final Answer:
The hormone that is not secreted by an endocrine gland is **Atrial Natriuretic Factor (ANF)**.

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