Rate of photosynthesis is independent of

Options

A. Intensity of light
B. Duration of light
C. Quality of light
D. Temperature.

Answer

To determine which factor the rate of photosynthesis is independent of, we can analyze each option provided in the question:

1. **Intensity of Light**: The intensity of light is a crucial factor that affects the rate of photosynthesis. Higher light intensity generally increases the rate of photosynthesis up to a certain point, beyond which it may plateau. Therefore, the rate of photosynthesis is dependent on the intensity of light.

2. **Quality of Light**: The quality (or wavelength) of light also plays a significant role in photosynthesis. Different wavelengths of light are absorbed by chlorophyll and other pigments, with red and blue light being most effective. Thus, the rate of photosynthesis is dependent on the quality of light.

3. **Temperature**: Temperature affects the enzymatic reactions involved in photosynthesis. Each enzyme has an optimal temperature range, and deviations from this range can decrease the rate of photosynthesis. Hence, the rate of photosynthesis is dependent on temperature.

4. **Duration of Light**: The duration of light refers to the length of time that light is available for photosynthesis. However, once a plant has received sufficient light for a certain period, extending that duration does not necessarily increase the rate of photosynthesis. Therefore, the rate of photosynthesis is independent of the duration of light.

Based on this analysis, the correct answer is that the rate of photosynthesis is independent of the **duration of light**.

### Step-by-Step Solution:
1. **Identify the factors affecting photosynthesis**: Consider the factors provided: intensity of light, quality of light, temperature, and duration of light.
2. **Analyze each factor**:
- Intensity of light: Increases the rate of photosynthesis.
- Quality of light: Different wavelengths affect the rate.
- Temperature: Affects enzyme activity and thus the rate.
- Duration of light: Once sufficient light is received, extending duration does not increase the rate.
3. **Determine independence**: Conclude that the rate of photosynthesis is independent of the duration of light.
4. **Select the correct option**: The answer is duration of light.