A process that makes important diference between `C_(3)` and `C_(4)` plants is

Options

A. Glycolysis
B. Photosynthesis
C. Photorespiration
D. Transpiration

Answer

To answer the question regarding the process that makes an important difference between C3 and C4 plants, we can follow these steps:

### Step-by-Step Solution:

1. **Understanding C3 and C4 Plants**:
- C3 plants are those that utilize the Calvin cycle for photosynthesis, where carbon dioxide is fixed directly into a three-carbon compound (3-phosphoglycerate).
- C4 plants, on the other hand, have a modified pathway that initially fixes carbon dioxide into a four-carbon compound (oxaloacetate) before it enters the Calvin cycle.

2. **Identifying Key Processes**:
- The question lists several processes: glycolysis, photosynthesis, photorespiration, and transpiration.
- Among these, we need to identify which process significantly differentiates C3 from C4 plants.

3. **Analyzing Photorespiration**:
- Photorespiration is a process that occurs in C3 plants when the enzyme RuBisCO oxygenates ribulose bisphosphate instead of carboxylating it.
- This leads to the production of a two-carbon compound instead of a three-carbon compound, resulting in the release of carbon dioxide and a decrease in photosynthetic efficiency.

4. **C4 Plants and Photorespiration**:
- C4 plants have evolved mechanisms to minimize photorespiration. They concentrate carbon dioxide in the bundle sheath cells, which reduces the likelihood of RuBisCO catalyzing the oxygenation reaction.
- Therefore, C4 plants generally do not experience photorespiration to the same extent as C3 plants.

5. **Conclusion**:
- The process that makes an important difference between C3 and C4 plants is **photorespiration**. C3 plants undergo photorespiration, while C4 plants have adaptations that significantly reduce or eliminate this process.

### Final Answer:
The important difference between C3 and C4 plants is **photorespiration**.

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