Growth hormone of pituitary is more effective in

Options

A. Presence of thyroxine
B. Absence of thyroxine
C. Absence of Insulin
D. Presence of adrenaline

Answer

**Step-by-Step Solution:**

1. **Understanding Growth Hormone (GH):**
- Growth hormone, also known as somatotropin, is produced by the anterior pituitary gland. It plays a crucial role in growth, metabolism, and body composition.

2. **Analyzing the Options:**
- The question asks in which condition the growth hormone is more effective. We have four options to evaluate.

3. **Option 1: Presence of Thyroxine**
- Thyroxine is a hormone produced by the thyroid gland that regulates metabolism. The presence of thyroxine enhances the effectiveness of growth hormone in stimulating growth and metabolism. Therefore, this option is likely correct.

4. **Option 2: Absence of Thyroxine**
- The absence of thyroxine leads to a decrease in metabolic rate, which negatively affects growth and overall metabolism. This option is incorrect.

5. **Option 3: Absence of Insulin**
- Insulin is crucial for glucose metabolism. If insulin is absent, glucose levels rise, leading to metabolic issues. This condition does not enhance the effectiveness of growth hormone, making this option incorrect.

6. **Option 4: Presence of Adrenaline**
- Adrenaline is a hormone released during stress (fight or flight response) and primarily affects heart rate and energy mobilization. It does not directly enhance the effectiveness of growth hormone, so this option is also incorrect.

7. **Conclusion:**
- After evaluating all options, the correct answer is **Option 1: Presence of Thyroxine**, as it enhances the effectiveness of growth hormone.

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