Question

why chlorophyll a is absent in the photosynthetic bacteria

Answer 1

In this article we will discuss about the presence of pigments in photosynthetic bacteria.

Because of the presence of carotenoids in all photosynthetic tissues their role is anticipated in photosynthesis. The tissue/cells rich in carotenoids devoid of chlorophyll do not photosynthesize. Light energy absorbed by carotenoids appears to be transferred to chlorophyll a or bacteriochlorophyll a and utilized in the photosynthesis.

It was observed if light is absorbed directly by chlorophyll a, generally found to be less efficient in photosynthesis than that of light absorbed by accessory pigments such as phycocyanin or phycoerythrin.

Answer 2

In photosynthetic bacteria's chlorophyll is absent this is because they contain bacteriochlorophyll which resembles chlorophyll and absorbs light of a longer wavelength than chlorophyll.

This is the reason of not present of chlorophyll in photosynthetic bacteria.

Hope it helps.....