Question

short notes on pigmentation in algae ​

Answer 1

All photosynthetic organisms contain one or more organic pigments capable of absorbing visible radiation, which will initiate the photochemical reactions of photosynthesis. The three major classes of pigments found in plants and algae are the chlorophylls, the carotenoids and the phycobilins. Carotenoid and phycobilins are called accessory pigments since the quanta (packets of light) absorbed by these pigments can be transferred to chlorophyll.

Three major classes of photosynthetic pigments occur among the algae: chlorophylls, carotenoids (carotenes and xanthophylls) and phycobilins. The pigments are characteristic of certain algal groups as indicated below. Chlorophylls and carotenes are generally fat soluble molecules and can be extracted from thylakoid membranes with organic solvents such as acetone, methanol or DMSO. The phycobilins and peridinin, in contrast, are water soluble and can be extracted from algal tissues after the organic solvent extraction of chlorophyll in those tissues.

Answer 2

Algae include three important kinds of photosynthetic pigments: chlorophylls, carotenoids (carotenes and xanthophylls), and phycobilins.

Pigmentation in algae:

• Except for Cyanophyceae members, pigments are typically present in specialized plastids termed chromophores in all species of algae (blue-green algae).
• Photosynthetic pigments are found in all algae.
• These are typically an intrinsic part of the structure of the chloroplast lamellae, but in certain cases, such as in blue-green algae, they are uniformly distributed throughout the protoplasm known as the "chromatoplasm."
• Pigments are light-absorbing compounds.

Classifications of algae:

• Chlorophyceae - These are known as green algae because they contain the pigments chlorophyll a and b.
• Phaeophyceae - Brown algae that are mostly found in the sea.
• Rhodophyceae are known as red algae due to the presence of the red pigment r-phycoerythrin.

#SPJ2