In cytochromes, electrons are picked up and released by

Options

A. Fe
B. Mo
C. Cu
D. Zn

Answer

**Step-by-Step Solution:**

1. **Understanding Cytochromes**: Cytochromes are proteins that play a crucial role in the electron transport chain, which is part of cellular respiration. They are involved in transferring electrons from one molecule to another.

2. **Structure of Cytochromes**: Cytochromes contain a heme group, which is a prosthetic group that is essential for their function. The heme group is a complex of iron and porphyrin.

3. **Role of Iron in Cytochromes**: The key component of the heme group is the iron atom. This iron atom is responsible for the redox reactions that occur in cytochromes. It can exist in multiple oxidation states, allowing it to accept and donate electrons.

4. **Identifying the Correct Answer**: Given the options (Iron, Molybdenum, Copper, Zinc), we need to determine which element is responsible for the electron transfer in cytochromes. Since we established that the iron atom in the heme group is responsible for picking up and releasing electrons, the correct answer is Iron.

5. **Conclusion**: Therefore, in cytochromes, electrons are picked up and released by Iron.

**Final Answer**: Iron

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