The `C_(3)` plants show ` CO_(2)` satruration

Options

A. At about `360 muL^(-1)`
B. Only below ` 450 muL^(-1)`
C. Only beyond `540 muL^(-1)`
D. only beyond ` 450muL^(-1)`

Answer

To solve the question regarding the CO₂ saturation levels in C₃ plants, we can follow these steps:

### Step-by-Step Solution:

1. **Understand CO₂ Saturation**: C₃ plants are known to have a certain threshold of CO₂ concentration at which the rate of photosynthesis reaches its maximum. Beyond this point, increasing CO₂ levels do not significantly enhance photosynthesis.

2. **Identify the CO₂ Concentration Levels**: According to the information provided, the CO₂ concentration in the atmosphere typically ranges from 0.03% to 0.04%. This translates to approximately 360 to 450 micro liters per liter (ppm).

3. **Determine the Saturation Point for C₃ Plants**: The saturation point for C₃ plants is indicated to be beyond 450 micro liters. This means that at concentrations higher than this level, the rate of photosynthesis does not increase further.

4. **Consider the Effects of High CO₂ Concentration**: While an increase in CO₂ concentration can initially boost photosynthesis, very high levels can inhibit the process. This is particularly relevant for C₃ plants, which can be adversely affected if CO₂ levels exceed their saturation point.

5. **Conclude the Answer**: Based on the information provided, the correct answer to the question is that C₃ plants show CO₂ saturation only beyond 450 micro liters.

### Final Answer:
C₃ plants show CO₂ saturation only beyond 450 micro liters.

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