Question

How do you know that green light is not absorbed by chlorophyll?

Answer 1

Hint: The chloroplast is the main organelle of green leaves which perform photosynthesis with the help of chlorophyll pigment. The different chlorophyll pigment absorbs light of different wavelength and colour of leaf depending upon the light gets reflected.

Complete answer:
In plants, the green leaves perform photosynthesis with the help of photosynthetic pigment present inside the chloroplast. The photosynthetic pigment present inside the leaves is chlorophyll a, chlorophyll b, xanthophyll and carotene, the chlorophyll pigments are the main pigments whereas remain is the accessory pigment. The chlorophyll-a pigment absorbs blue-violet light of wavelength 400-450 nm and chlorophyll b pigment absorbs the red light of wavelength 700 nm therefore between this pigment absorption does not take place. The green light has the wavelength of 550 nm which lies between the wavelength of 450- 700 nm therefore green light gets reflected by chlorophyll. Due to the absorption of blue, violet and red light, and the reflection of green light the leaves of the higher plant appear green in colour. The xanthophyll pigment of leaves absorb the light of yellow colour and carotene pigment absorb the light of yellow to a yellow-orange colour. The light energy which gets absorbed by the pigment inside the chloroplast helps in the synthesis of ATP and NADPH during photosynthesis.

Note:
The chloroplast shows phototactic movement in higher plants. Under strong light, the chloroplast gets aligned with the wall of mesophyll cell longitudinally whereas under moderate light the chloroplast gets arranged perpendicularly to the incident light. The perpendicular arrangement of the chloroplast is called apostrophe whereas the longitudinal arrangement is known as parastrophe.