Choose the incorrect statement regarding hemoglobin .

Options

A. It is red coloured pigment
B. It contains iron
C. It is present inside RBC
D. It binds with oxygen irreversibly

Answer

**Step-by-Step Solution:**

1. **Understanding Hemoglobin**: Hemoglobin is a red-colored protein found in red blood cells (RBCs). It plays a crucial role in transporting oxygen from the lungs to the rest of the body.

2. **Composition of Hemoglobin**: Hemoglobin contains iron, which gives it the ability to bind with oxygen. This binding is essential for oxygen transport.

3. **Location of Hemoglobin**: Hemoglobin is present inside red blood cells. This is why RBCs are often referred to as red blood cells, due to the red pigment of hemoglobin.

4. **Binding Characteristics**: The statement in question claims that hemoglobin binds with oxygen irreversibly. This is incorrect. Hemoglobin binds to oxygen in the lungs and then releases it in the tissues where it is needed.

5. **Reversibility of Binding**: The binding of hemoglobin with oxygen is reversible. This means that hemoglobin can pick up oxygen in the lungs and release it in the tissues, which is a vital function for maintaining oxygen levels in the body.

6. **Conclusion**: Since the statement that hemoglobin binds with oxygen irreversibly is incorrect, this is the answer to the question.

**Final Answer**: The incorrect statement regarding hemoglobin is that it binds with oxygen irreversibly.

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