Write the concentration of `CO_(2)` at which `C_(3) and C_(4)` plants shows saturation respectively.

Answer

To answer the question regarding the concentration of CO₂ at which C₃ and C₄ plants show saturation, we can follow these steps:

### Step-by-Step Solution:

1. **Understanding Photosynthesis**: Photosynthesis is the process by which plants convert carbon dioxide (CO₂) and sunlight into glucose and oxygen. The rate of photosynthesis can be influenced by the concentration of CO₂.

2. **CO₂ Concentration in Atmosphere**: The natural concentration of CO₂ in the atmosphere is approximately 0.03 to 0.04 percent. This is equivalent to about 300 to 400 parts per million (ppm).

3. **Effect of Increased CO₂**: As the concentration of CO₂ increases, the rate of photosynthesis also increases up to a certain point. This is known as the saturation point.

4. **Saturation Point for C₃ Plants**: C₃ plants typically show saturation at around 450 ppm of CO₂. This means that at this concentration, increasing CO₂ further does not significantly enhance the rate of photosynthesis.

5. **Saturation Point for C₄ Plants**: In contrast, C₄ plants reach their saturation point at a lower concentration of CO₂, which is approximately 360 ppm.

6. **Conclusion**: Therefore, the concentrations of CO₂ at which C₃ and C₄ plants show saturation are 450 ppm and 360 ppm, respectively.

### Final Answer:
- C₃ plants show saturation at **450 ppm**.
- C₄ plants show saturation at **360 ppm**.