Each haemoglobin molecule has

Options

A. One heme group
B. Two heme groups
C. Three heme groups
D. Four heme groups

Answer

To answer the question "Each hemoglobin molecule has," we can break it down into the following steps:

### Step-by-Step Solution:

1. **Understanding Hemoglobin Structure**:
- Hemoglobin is a protein found in red blood cells that is responsible for transporting oxygen from the lungs to the rest of the body and returning carbon dioxide from the body back to the lungs.

2. **Identifying Components of Hemoglobin**:
- Each hemoglobin molecule is made up of four subunits. Each subunit consists of a globin chain (a protein part) and a heme group (an iron-containing compound).

3. **Counting Heme Groups**:
- Each hemoglobin molecule contains four heme groups. These heme groups are crucial because they bind to oxygen molecules.

4. **Final Conclusion**:
- Therefore, the answer to the question is that each hemoglobin molecule has **four heme groups**.

### Answer:
Each hemoglobin molecule has **four heme groups**.

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