Algae are divided into three main classes. What are the three classes? Differentiate them on the basis of photosynthetic pigment and food.

Algae are divided into three classes. The presence or absence of pigments is the main basis of the classification of algae. Following are three classes of algae:-

1. Chlorophyceae: Chlorophyll a and b are present in them and impart a green color. Chlorophyceae are also called ‘green algae’.

2. Phaeophyceae: Chlorophyll a and c and fucoxanthin are present. Fucoxanthin imparts brown color. Phaeophyceae are also called ‘brown algae’.

3. Rhodophyceae: Chlorophyll a and d and phycoerythrin are present. Phycoerythrin imparts red color. Rhodophyceae are also called ‘red algae’.