Which group of three micronutrient elements is required for both photosynthesis and mitochondrial electron transport ?

Options

A. Cu, Mn, Fe
B. Co, Ni, Mo
C. Ca, K, Na
D. Mn, Co, Ca

Answer

To solve the question regarding which group of three micronutrient elements is required for both photosynthesis and mitochondrial electron transport, we can follow these steps:

### Step-by-Step Solution:

1. **Identify the Micronutrients**: We need to identify the micronutrients that play a role in both photosynthesis and mitochondrial electron transport. The three micronutrients we will consider are copper (Cu), manganese (Mn), and iron (Fe).

2. **Role of Copper (Cu)**:
- Copper is an essential micronutrient that acts as an activator for several enzymes involved in photosynthesis.
- Specifically, it is a cofactor for enzymes like plastocyanin, cytochrome oxidase, and ribulose bisphosphate (RuBP) carboxylase, which are crucial for the photosynthetic process.

3. **Role of Manganese (Mn)**:
- Manganese is another important micronutrient that activates various enzymes involved in both respiration and photosynthesis.
- It is known to be involved in the oxygen-evolving complex of photosystem II and also plays a role in the metabolism of carbohydrates.

4. **Role of Iron (Fe)**:
- Iron is a critical component of many proteins involved in electron transport, such as ferredoxin and cytochrome.
- It facilitates the transfer of electrons during both photosynthesis and cellular respiration, making it essential for mitochondrial electron transport.

5. **Conclusion**:
- After analyzing the roles of these three micronutrients, we conclude that copper (Cu), manganese (Mn), and iron (Fe) are required for both photosynthesis and mitochondrial electron transport.

### Final Answer:
The group of three micronutrient elements required for both photosynthesis and mitochondrial electron transport is **Copper (Cu), Manganese (Mn), and Iron (Fe)**.

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