Enhancement Effect for the rate of Photosynthesis, observed by Emerson is possible in the presence of

Options

A. shorter wavelength of light
B. shorter wavelength of light
C. infrared wavelength
D. a combination of longer and shorter wavelength of light

Answer

**Step-by-Step Solution:**

1. **Understanding the Enhancement Effect**: The enhancement effect refers to the increased rate of photosynthesis that occurs when two different wavelengths of light are used simultaneously. This phenomenon was first observed by the scientist Robert Emerson.

2. **Identifying the Wavelengths**: Robert Emerson studied the effects of two specific wavelengths of light on photosynthesis:
- Red light (around 680 nm)
- Far-red light (around 700 nm)

3. **Combining Wavelengths**: Emerson found that when both red light and far-red light were present, the rate of photosynthesis was significantly higher than when either light was used alone. This indicates that a combination of different wavelengths can enhance the photosynthetic process.

4. **Evaluating the Options**: The question asks for the condition under which the enhancement effect is possible. The options provided include:
- Shorter wavelength
- Both shorter wavelength
- Both infrared wavelength
- A combination of longer and shorter wavelengths of light

5. **Selecting the Correct Option**: The correct answer is the last option: "a combination of longer and shorter wavelengths of light." This is because the enhancement effect is observed when both red (shorter wavelength) and far-red (longer wavelength) lights are used together.

**Final Answer**: The enhancement effect for the rate of photosynthesis observed by Emerson is possible in the presence of a combination of longer and shorter wavelengths of light.

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