Which part of human body is the first to be affected by nuclear radiations?

Options

A. Bone marrow
B. Liver
C. Lungs
D. Brain

Answer

**Step-by-Step Solution:**

1. **Understanding the Question**: The question asks which part of the human body is the first to be affected by nuclear radiation. This requires knowledge of how nuclear radiation interacts with human tissues.

2. **Identifying the Options**: The options provided are:
- Option 1: Bone marrow
- Option 2: Liver
- Option 3: Lungs
- Option 4: Brain

3. **Analyzing Each Option**:
- **Bone Marrow**: This is the site of blood cell production, including red blood cells (RBCs), white blood cells (WBCs), and platelets. Given that blood cells are crucial for the immune system and overall health, any damage to the bone marrow can severely impact the body.
- **Liver**: While the liver is vital for detoxification and metabolism, it is not the first organ affected by radiation exposure.
- **Lungs**: The lungs are primarily involved in gas exchange and are not directly affected by radiation in the same way as the bone marrow.
- **Brain**: The brain is critical for neurological functions but is not the first organ to show effects from radiation exposure.

4. **Conclusion**: Based on the analysis, bone marrow is the first part of the human body to be affected by nuclear radiation due to its role in producing blood cells, which are essential for the body's functioning.

5. **Final Answer**: The correct answer is **Bone Marrow**.

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