In which state iron is present in haemoglobin.

Options

A. Unironic
B. `Fe^(2+)`
C. `Fe^(3+)`
D. None of the above

Answer

To determine the state in which iron is present in hemoglobin, we can follow these steps:

### Step-by-Step Solution:

1. **Understanding Hemoglobin**:
- Hemoglobin is a protein found in red blood cells (RBCs) that is essential for transporting oxygen throughout the body.

2. **Role of Iron in Hemoglobin**:
- Iron is a crucial component of hemoglobin, as it is the element that binds to oxygen molecules.

3. **Identifying the Ionic States of Iron**:
- Iron can exist in different ionic states, primarily:
- **Ferrous (Fe²⁺)**: This is the reduced form of iron.
- **Ferric (Fe³⁺)**: This is the oxidized form of iron.
- **Unironic**: This term does not apply to iron in hemoglobin.

4. **Binding of Oxygen**:
- For hemoglobin to effectively bind oxygen, iron must be in the ferrous state (Fe²⁺). This is because oxygen can only attach to iron when it is in this reduced form.

5. **Conclusion**:
- If iron were in the ferric state (Fe³⁺), it would not be able to bind with oxygen, rendering hemoglobin ineffective in its primary function of oxygen transport.

6. **Final Answer**:
- Therefore, the state of iron present in hemoglobin is **ferrous (Fe²⁺)**.