The visible portion of light spectrum useful in photosynthesis is referred to as

Options

A. RFLP
B. PAR
C. VAM
D. VNTR.

Answer

To answer the question regarding the visible portion of the light spectrum useful in photosynthesis, we can follow these steps:

### Step-by-Step Solution:

1. **Understanding Photosynthesis**: Photosynthesis is the process by which green plants, algae, and some bacteria convert light energy into chemical energy, using carbon dioxide and water, producing glucose and oxygen as byproducts.

2. **Role of Light in Photosynthesis**: Light is essential for photosynthesis. However, not all wavelengths of light are effective in driving this process.

3. **Identifying the Useful Light Spectrum**: The visible portion of the light spectrum that is useful for photosynthesis is specifically referred to as Photosynthetically Active Radiation (PAR).

4. **Defining PAR**: PAR encompasses the wavelengths of light that plants can use for photosynthesis, which typically ranges from approximately 400 to 700 nanometers.

5. **Percentage of Total Light**: It is important to note that PAR constitutes about 2% of the total incident light from the sun that reaches the Earth.

6. **Conclusion**: Therefore, the visible portion of the light spectrum useful in photosynthesis is known as PAR, which stands for Photosynthetically Active Radiation.

### Final Answer:
The visible portion of the light spectrum useful in photosynthesis is referred to as **Photosynthetically Active Radiation (PAR)**.

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