The microelement which is an integral part of electron carrier that transfers electrons electrons from cyt b-f complex to PS I is also a component of

Options

A. Nitrate reductase
B. Cytochrome c-oxidase
C. IAA-oxidase
D. Dinitrogenase.

Answer

To solve the question regarding the microelement that is an integral part of the electron carrier transferring electrons from the cytochrome b-f complex to Photosystem I (PSI), we can follow these steps:

### Step-by-Step Solution:

1. **Understand the Components**: The question refers to the electron transport chain in photosynthesis, specifically the transfer of electrons from the cytochrome b-f complex to PSI.

2. **Identify the Electron Carrier**: The electron carrier that transfers electrons from the cytochrome b-f complex to PSI is known as plastocyanin.

3. **Determine the Microelement**: Plastocyanin is a copper-containing protein. Therefore, the microelement that is integral to plastocyanin is copper (Cu).

4. **Relate to Other Components**: The question also asks what other component this microelement is a part of. In the context of cellular respiration, copper is also a component of cytochrome c oxidase, which is part of the electron transport chain in mitochondria.

5. **Conclusion**: The microelement that is integral to the electron carrier (plastocyanin) and is also a component of another important protein (cytochrome c oxidase) is copper.

### Final Answer:
The microelement which is an integral part of the electron carrier that transfers electrons from the cytochrome b-f complex to PSI is **copper**.

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