Suppose there were plants that had a high concentration of Chlorophyll-b, but lacked chlorophyll-a, would it carry out photosynthesis? Then why do plants have chlorophyll-b and other accessory pigments?

Explanation

Photosynthesis cannot be carried out without the presence of pigment chlorophylla. This acts as a reaction centre. Chl `a_(700)` acts as a reaction centre of PS - I and Chl`a_(680 )` acts as a reaction centre of PS-II. Chlorophyllb and other accessory pigments are able to absorb shorter wavelengths and then transfer their energy to chla for photophosphorylation. Such accessory pigments not only enable a wider range of wavelength of incoming light to be used for photosynthesis but also protect chlorophyll a from photo-oxidation.