Question

The most important function of chlorophyll is:
(a) Absorb carbon dioxide from the atmosphere
(b) Absorb water and minerals from the soil
(c) Give green colour to the leaves
(d) perform photosynthesis in the presence of sunlight

Answer 1

Hint: Chlorophyll is a key component in the process which sustains plant life and produces oxygen for the entire planet. It is present in the chloroplast, an organelle exclusively found in plants.

Complete answer:
Chlorophyll is a light-absorbing green pigment present in chloroplast along with many other photosynthetic pigments. It is an essential pigment to perform photosynthesis as it can convert light energy into chemical energy (ATP). Other pigments act as accessory pigments because they collect and transfer light energy to chlorophyll-a for photosynthesis.

Additional Information: Photosynthesis is an enzyme regulated process inside chloroplast to produce glucose from carbon dioxide and water in the presence of sunlight. Stomata are tiny epidermal pores on leaves helping in the entry of carbon dioxide. The requirement of water is fulfilled from the soil by roots. Light energy is absorbed by photosynthetic pigments and converted into ATP by chlorophyll.
A pigment is a molecule that can absorb light at different wavelengths and thus has a particular colour. Chlorophyll absorbs light radiations in blue and red parts of the light spectrum. Chlorophyll is mostly present in two forms- chlorophyll-a and chlorophyll-b. Chlorophyll a absorbs more red wavelengths than violet-blue wavelengths of light while Chlorophyll-b absorbs violet-blue wavelengths more than the red wavelength of light.

So, the correct answer is 'perform photosynthesis in the presence of sunlight'.

Note: Accessory pigments include carotenoids, carotenes and xanthophylls and protect the chloroplast from nascent oxygen released during the photolysis of water. They dissipate excess energy by conversion of that energy into heat. Also, they make the flowers and fruits conspicuous to animals for pollination and dispersal.