For their functioning, cytochromes possess

Options

A. Mg
B. Fe
C. Mn
D. Na.

Answer

**Step-by-Step Solution:**

1. **Understanding Cytochromes:**
- Cytochromes are proteins that play a crucial role in the electron transport chain, which is a part of cellular respiration.

2. **Identifying Key Components:**
- The key component of cytochromes is the porphyrin ring. This structure is essential for their function.

3. **Role of Iron:**
- Within the porphyrin ring, cytochromes contain iron (Fe). This iron can exist in different oxidation states, specifically Fe²⁺ (ferrous), Fe³⁺ (ferric), and even Fe⁴⁺.

4. **Function of Iron in Cytochromes:**
- The iron in cytochromes is responsible for electron transfer. It undergoes reduction (gaining electrons) and oxidation (losing electrons) during the electron transport process.

5. **Conclusion:**
- Therefore, for their functioning, cytochromes possess iron (Fe) as a critical component for electron transfer.

**Final Answer:**
Cytochromes possess iron (Fe) for their functioning.

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