Name three main classes of algae with examples and write the pigments present in them.

1. Chlorophyceae: (Green algae), Chlorophyll a & b e.g. Chlamydomonas, Volvox, Spirogyra.

2. Phaeophyceae (Brown algae), chlorophyll a & c and fucoxanthin e.g. Laminaria, Sargassum and Fucus.

3. Rhodophyceae (Red algae): Chlorophyll a, d and phycoerythrin e.g. Porphyra, Gelidium, Gracilaria.