Cytochrome oxidase has

Options

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

Explanation

**Step-by-Step Solution:**

1. **Understanding Cytochrome Oxidase**: Cytochrome oxidase is an important enzyme found in the electron transport chain of mitochondria. It plays a crucial role in cellular respiration by facilitating the transfer of electrons to oxygen.

2. **Identifying Key Components**: The enzyme contains specific metal ions that are essential for its function. The two primary metal ions associated with cytochrome oxidase are iron (Fe) and molybdenum (Mo).

3. **Role of Iron (Fe)**: Iron is a critical component of cytochrome oxidase. It serves as an electron gate, meaning it helps in the transfer of electrons during the redox reactions that occur in cellular respiration.

4. **Role of Molybdenum (Mo)**: Molybdenum is also a trace element that plays a role in various enzymatic processes, including nitrogen fixation in plants. However, its direct role in cytochrome oxidase is less prominent compared to iron.

5. **Conclusion**: Based on the components and their roles, cytochrome oxidase has iron (Fe) as a significant element that facilitates its function in electron transport.

**Final Answer**: Cytochrome oxidase has iron (Fe) as a key component.

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