Which range of wavelength (in nm) is called photosynthetically active radiation (PAR) ? 

1.  100 - 390

2.  390-430

3. 400 - 700 

4. 760- 100,00

Which light  range is most effective in photosynthesis ? 

1.  Blue 

2. Green 

3. Red 

4. Violet 

Chemosynthetic bacteria obtain energy from 

1. Sun 

2. Infra red rays 

3. Organic substances 

4. Inorganic chemicals