Question

Photosynthetic pigments of cyanobacteria (blue-green algae) include
(a) Chlorophyll a
(b) Carotenes
(c) Xanthophylls
(d) All of these

Answer 1

 
Hint: Cyanobacteria or blue-green algae are prokaryotic organisms that are capable of producing their food by the process of photosynthesis. Photosynthesis requires certain coloured pigments to harness light energy. Cyanobacteria have pigments of various colours like green, orange, red, and yellow that help in photosynthesis.

Complete Step by Step Answer:
Cyanobacteria or blue-green algae are photosynthetic prokaryotes that can harness light energy and convert it into chemical energy. They do so with the help of certain pigments such as the Chlorophyll a, Carotene and Xanthophylls.
Chlorophyll a is a form of chlorophyll that is used in oxygenic photosynthesis. It absorbs most energy from the violet-blue and orange-red spectrum of the visible light. They act as an electron acceptor in the electron transport chain.
Carotenes and Xanthophylls belong to a group of pigments called Carotenoids.
Carotenes are red-orange coloured pigments and xanthophylls are yellow coloured pigments. Carotenoids too help in the absorption of light for the process of photosynthesis as they can entrap the photons and through photosystems then convert it into chemical energy.
So, the correct answer is, “All of these.”

Note:
- Xanthophylls and Carotenoids are present in flowers and fruits too and provide colour to them.
- Carotenoids give the characteristic reddish- orange and yellow colour to pumpkins, carrots, corn, tomatoes, and daffodils. They are pigments that are also present in animal tissues and animal products to give the yellow and red colour.
- Chlorophylls are of various types, of which Chlorophyll a is a universal pigment which is present in all photosynthetic organisms.