Blood pressure and heart beat is regulated by `:-`

Options

A. Insulin
B. Adrenalin
C. Optic nerve
D. Growth hormone

Answer

To answer the question "Blood pressure and heart beat is regulated by:", we will analyze each option provided and determine which one is correct.

### Step-by-Step Solution:

1. **Evaluate Option A: Insulin**
- Insulin is a hormone secreted by the pancreas.
- Its primary function is to regulate glucose levels in the blood by facilitating the absorption of glucose into cells.
- Insulin does not play a role in regulating blood pressure or heart rate.
- **Conclusion**: Option A is incorrect.

2. **Evaluate Option B: Adrenaline**
- Adrenaline (also known as epinephrine) is a hormone and neurotransmitter produced by the adrenal glands.
- It is involved in the body's fight-or-flight response and has significant effects on heart rate and blood pressure.
- Adrenaline increases heart rate and constricts blood vessels, which raises blood pressure.
- **Conclusion**: Option B is correct.

3. **Evaluate Option C: Optic Nerve**
- The optic nerve is responsible for transmitting visual information from the retina to the brain.
- It does not have any role in the regulation of blood pressure or heart rate.
- **Conclusion**: Option C is incorrect.

4. **Evaluate Option D: Growth Hormone**
- Growth hormone is produced by the pituitary gland and is primarily involved in growth and metabolism.
- It does not directly influence heart rate or blood pressure regulation.
- **Conclusion**: Option D is incorrect.

### Final Answer:
The correct option for the regulation of blood pressure and heart beat is **Option B: Adrenaline**.

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