The wavelength of PAR (photosynthesis active radiation) is

Options

A. 40-70 nm
B. 400-700 nm
C. `400-700 Å`
D. `40-70 Å`

Answer

**Step-by-Step Solution:**

1. **Understanding PAR:**
- Photosynthetically Active Radiation (PAR) refers to the spectrum of light that plants use for photosynthesis. It is crucial for the process where plants convert light energy into chemical energy.

2. **Identifying the Wavelength Range:**
- The specific range of wavelengths that constitutes PAR is essential for understanding how plants utilize light.

3. **Determining the Correct Wavelength Range:**
- The range of wavelengths for PAR is from 400 nanometers (nm) to 700 nanometers (nm). This range includes the visible light spectrum that plants can absorb and use for photosynthesis.

4. **Evaluating Options:**
- Given options may include ranges that are incorrect. The correct wavelength range for PAR is 400 to 700 nm.

5. **Conclusion:**
- Therefore, the correct answer to the question regarding the wavelength of PAR is 400 to 700 nanometers.

**Final Answer:**
The wavelength of PAR (photosynthetically active radiation) is 400 to 700 nanometers.

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