Abstract:

Algae are unicellular and multicellular organisms that occur in fresh water, marine water, and damp terrestrial environments. All algae possess chlorophyll a, the green pigment essential for photosynthesis. Algae may contain additional pigments, such as fucoxanthin (brown) or phycoerythrin (red), which can mask the green color of chlorophyll. The life cycle of algae may be simple, involving cell division, or complex, involving alternation of generations. Algae are primary producers of the organic matter upon which animals depend either directly or indirectly through the food chain.