Which theory explains ATP synthesis in chloroplasts and mitochondira ?

Options

A. Lipman and Lohmann theory
B. Lock and key theory of Fischer
C. Induced fit theory of Fischer
D. Chemi-osmotic theory of Mitchell.

Answer

**Step-by-Step Solution:**

1. **Understanding the Question**: The question asks for the theory that explains ATP synthesis in chloroplasts and mitochondria. ATP (adenosine triphosphate) is the primary energy currency in cells, and its synthesis is crucial for cellular functions.

2. **Identifying the Options**: The options provided are:
- Lippmann and Lohmann theory
- Lokenky theory of Fischer
- Induced fit theory of Fischer
- Chemiosmotic theory of Mitchell

3. **Analyzing Each Option**:
- **Lippmann and Lohmann theory**: This theory relates to the discovery of ATP but does not specifically explain its synthesis in chloroplasts and mitochondria.
- **Lokenky theory of Fischer**: This option is not well-known in the context of ATP synthesis and does not pertain to the question.
- **Induced fit theory of Fischer**: This theory describes the interaction between enzymes and substrates, focusing on how enzymes change shape upon substrate binding. It does not relate to ATP synthesis.
- **Chemiosmotic theory of Mitchell**: This theory explains how ATP is synthesized in both chloroplasts and mitochondria through processes known as oxidative phosphorylation (in mitochondria) and photophosphorylation (in chloroplasts).

4. **Conclusion**: Based on the analysis, the correct answer is the **Chemiosmotic theory of Mitchell**. This theory is fundamental in understanding how energy from electron transport is used to create a proton gradient, which drives ATP synthesis.

5. **Final Answer**: The theory that explains ATP synthesis in chloroplasts and mitochondria is the **Chemiosmotic theory of Mitchell**.

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