How many heme molecules are present in one molecule of haemoglobin ?

Options

A. 1
B. 2
C. 3
D. 4

Answer

To determine how many heme molecules are present in one molecule of hemoglobin, we can follow these steps:

### Step-by-Step Solution:

1. **Understand Hemoglobin Structure**: Hemoglobin is a complex protein found in red blood cells (RBCs) that is responsible for transporting oxygen throughout the body. It consists of two main components: heme and globin.

2. **Identify the Components**:
- **Heme**: This is the pigment part of hemoglobin that contains iron and binds to oxygen.
- **Globin**: This is the protein part that surrounds the heme groups.

3. **Determine the Number of Heme Molecules**:
- Each hemoglobin molecule is made up of four polypeptide chains (two alpha and two beta chains).
- Each of these chains is associated with one heme group.

4. **Conclusion**: Since there are four polypeptide chains in one hemoglobin molecule, there are also four heme molecules present in one molecule of hemoglobin.

Thus, the answer is that there are **4 heme molecules** in one molecule of hemoglobin.

### Final Answer:
**4 heme molecules are present in one molecule of hemoglobin.**

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