`HbA_(2)` is composed of `:-`

Options

A. `alpha_(2),beta_(2)`
B. `alpha_(2) gamma_(2)`
C. `alpha_(2) delta_(2)`
D. `alpha_(2)alpha_(2)`

Answer

**Step-by-Step Solution:**

1. **Understanding Hemoglobin (Hb):** Hemoglobin is a protein in red blood cells that is responsible for transporting oxygen throughout the body. It gives blood its red color.

2. **Types of Hemoglobin:** There are different types of hemoglobin present in human blood. The most common type is HbA1, which is composed of two alpha (α) chains and two beta (β) chains, denoted as α2β2.

3. **Identifying HbA2:** HbA2 is another form of hemoglobin found in the blood, but it differs from HbA1 in its composition.

4. **Composition of HbA2:** HbA2 is composed of two alpha (α) chains and two delta (Δ) chains, represented as α2Δ2.

5. **Presence in Blood:** HbA2 is present in small amounts in normal individuals, typically ranging from 1% to 3% of total hemoglobin. It can also be elevated in certain conditions such as beta thalassemia and sickle cell anemia.

6. **Final Answer:** Therefore, HbA2 is composed of α2Δ2 chains.

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