Wavelengths of which of the following colours of the visible spectrum of light are maximally absorbed by green plants ?

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Q: 100 (CDS-I/2009)
Wavelengths of which of the following colours of the visible spectrum of light are maximally absorbed by green plants ?

question_subject: 

Science

question_exam: 

CDS-I

stats: 

0,67,66,28,67,24,14

keywords: 

{'wavelengths': [0, 0, 1, 2], 'green plants': [1, 0, 0, 1], 'green': [4, 0, 4, 6], 'colours': [0, 2, 4, 9], 'visible spectrum': [0, 0, 2, 0], 'yellow': [1, 1, 4, 3], 'blue': [0, 1, 0, 0], 'red': [1, 0, 0, 0], 'light': [16, 4, 34, 62]}

The correct answer is option 2: Red and Blue.

Green plants appear green to our eyes because they reflect green light and absorb other colors of the visible spectrum. The absorption of light by plants is mainly done by pigments called chlorophylls, which are primarily responsible for photosynthesis.

The absorption spectra of chlorophylls show that they absorb light most efficiently in the red and blue regions of the spectrum. They absorb very little green light, which is why plants reflect green light and appear green to us.

Option 1 (Green and Yellow) is incorrect because green light is not maximally absorbed by green plants; in fact, it is minimally absorbed. Yellow light is also not maximally absorbed by green plants.

Option 3 (Green and Red) is incorrect because green light is not maximally absorbed by green plants. While it is true that red light is absorbed to some extent by plants, it is not maximally absorbed.

Option 4 (Blue and Yellow) is incorrect because yellow light is not maximally absorbed by green plants. While blue light is absorbed by plants, it is not maximally absorbed.

Therefore, the correct answer is option 2: Red and Blue.