Question

3 Amongst red, blue and violet wavelength, which one is the most efficient photosynthesis ?
A.red
B.blue
C.violet
D.none of the above

Answer 1

Hint: Generally the blue wavelength is absorbed by the carotenoids which are passing their energy to the chlorophyll which is absorbing red light of the region.

Complete step by step answer:
The correct answer is red wavelength, because it is having longer wavelength, which is absorbed by the chlorophyll. This is also effective in photosynthesis, because it contains the right amount of energy to excite. Red light is more effective in photosynthesis because both the photosystems- PS I and PS II absorb light of wavelength in the red region i.e; 680 and 700 nm respectively. Furthermore blue light is absorbed by carotenoids, which pass energy to the chlorophyll, whereas the light in the red region is absorbed by chlorophyll.
Additional information: light is an essential factor for photosynthesis. There is a linear relationship between incident light and CO2 fixation at low light intensities. At higher light intensities, gradually the rate does not show further increase as other factors become limiting.

Hence the correct answer is option(A)

Note: Blue light is also effective but not equal to the red wavelength. Violet is less sufficient as compared to blue and red. Red and blue wavelengths have shorter wavelengths. Chlorophyll a, which is present in all photosynthetic organisms absorbs blue light with wavelength of 430 nm and red light of 662 nm. Chlorophyll B absorbs light of 453 nm and 642 nm. Carotenoids absorb green light between 460 nm and 550 nm.