In mature mammalian erythrocytes, the respiration is

Options

A. Aerobic
B. Anaerobic
C. Sometimes aerobic and sometimes anaerobic
D. Absent

Answer

**Step-by-Step Solution:**

1. **Understanding Erythrocytes**:
- Erythrocytes, commonly known as red blood cells (RBCs), are specialized cells in the blood that primarily function to transport oxygen throughout the body.

2. **Structure of Erythrocytes**:
- Mature mammalian erythrocytes are characterized by their oval biconcave disc shape. This shape increases their surface area for gas exchange.

3. **Absence of Organelles**:
- Mature erythrocytes lack a nucleus and most organelles, including mitochondria. This adaptation allows them to maximize space for hemoglobin, the protein responsible for oxygen transport.

4. **Respiration in Erythrocytes**:
- Respiration in cells typically occurs in two forms: aerobic (requiring oxygen) and anaerobic (not requiring oxygen). Aerobic respiration requires mitochondria to produce energy efficiently.

5. **Conclusion on Erythrocyte Respiration**:
- Since mature mammalian erythrocytes do not have mitochondria, they cannot perform aerobic respiration. Instead, they rely on anaerobic respiration to generate energy.

6. **Final Answer**:
- Therefore, the correct answer to the question is that in mature mammalian erythrocytes, respiration is **anaerobic**.

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