Adult Hb has chain `:-`

Options

A. `2 alpha, 2 beta`
B. `2alpha , 2 gamma `
C. `2 alpha , 2 delta`
D. ` 4 alpha`

Answer

**Step-by-Step Solution:**

1. **Understanding Hemoglobin**: Hemoglobin (Hb) is a respiratory pigment found in red blood cells that is responsible for transporting oxygen from the lungs to the tissues and carrying carbon dioxide back to the lungs.

2. **Composition of Adult Hemoglobin**: Adult hemoglobin, specifically Hemoglobin A (HbA), is composed of four polypeptide chains. These chains are classified into two types: alpha (α) and beta (β).

3. **Identifying the Chains**: In adult hemoglobin, there are two alpha chains and two beta chains. Thus, the composition can be summarized as:
- 2 Alpha (α) chains
- 2 Beta (β) chains

4. **Conclusion**: Therefore, the correct answer to the question "Adult Hb has chain :-" is "2 alpha and 2 beta chains."

5. **Final Answer**: Adult Hb has chains of 2 alpha and 2 beta.

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