Haemoglobin contains

Options

A. `Fe^(++)`
B. `Mg^(++)`
C. `Na^(++)`
D. `Ca^(++)`

Answer

**Step-by-Step Solution:**

1. **Understanding Hemoglobin**: Hemoglobin is a protein found in red blood cells that is responsible for transporting oxygen throughout the body.

2. **Composition of Hemoglobin**: Hemoglobin consists of four polypeptide chains (two alpha and two beta chains) and contains a heme group.

3. **Heme Group**: The heme group is a prosthetic group that is crucial for the function of hemoglobin. It is composed of a porphyrin ring with an iron atom at its center.

4. **Role of Iron**: The iron atom in the heme group is essential for binding oxygen. Each iron atom can bind one molecule of oxygen, allowing hemoglobin to carry up to four oxygen molecules.

5. **Percentage of Iron in Hemoglobin**: Hemoglobin contains approximately 0.334% of its weight as iron, which highlights the importance of iron in its structure and function.

6. **Identifying the Correct Answer**: Given the options (Fe +2, Mg +2, Na +2, Ca +2), the correct answer is Fe +2, as it is the only option that corresponds to the iron present in the heme group of hemoglobin.

**Final Answer**: Hemoglobin contains Fe +2.

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