Effect of thyroxine on B.M.R is

Options

A. Increase
B. Decrease
C. Uncertain
D. No effect

Answer

### Step-by-Step Solution:

1. **Understanding the Terms**:
- First, we need to understand what BMR (Basal Metabolic Rate) is. BMR refers to the rate at which the body expends energy at rest to maintain vital functions such as breathing, circulation, and cell production.

2. **Role of Thyroxine**:
- Thyroxine is a hormone produced by the thyroid gland. It plays a crucial role in regulating metabolism, including BMR.

3. **Effect of Thyroxine on BMR**:
- When the levels of thyroxine in the body are increased, it leads to an increase in the BMR. This means that the body burns more calories at rest when thyroxine levels are high.

4. **Conclusion**:
- Therefore, the effect of thyroxine on BMR is that it increases the BMR. Thus, the correct answer to the question is that thyroxine increases the BMR.

### Final Answer:
The effect of thyroxine on BMR is that it increases the BMR.

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