Which element or mineral is essential for electron transport system in both cristae and thylakoids ?

Options

A. Iron
B. Calcium
C. Potassium
D. Magnesium

Answer

**Step-by-Step Solution:**

1. **Understanding the Electron Transport Chain (ETC):**
- The electron transport chain is a series of complexes that transfer electrons through a membrane, ultimately leading to the production of ATP. It is present in both mitochondria (in the cristae) and chloroplasts (in the thylakoids).

2. **Identifying the Locations:**
- In mitochondria, the ETC is located in the inner membrane, which is folded into structures called cristae.
- In chloroplasts, the ETC is found in the thylakoid membranes, which are stacked to form grana.

3. **Role of Minerals in ETC:**
- Various minerals and elements are involved in the functioning of the ETC. They play crucial roles in the transfer of electrons.

4. **Key Element for Electron Transport:**
- The essential element for the electron transport system in both cristae and thylakoids is **iron (Fe)**.

5. **Reason for Iron's Importance:**
- Iron can exist in two oxidation states: ferrous (Fe²⁺) and ferric (Fe³⁺). This ability to switch between oxidation states allows iron to participate in redox reactions, which are fundamental to the electron transport process.

6. **Conclusion:**
- Therefore, the correct answer to the question is **iron (Fe)**, as it is the mineral essential for the electron transport system in both cristae and thylakoids.

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