Encyclopedia of Science | Algae

• Types of algae
• Words to Know
• Ecological importance of algae
• Algal Blooms
• Economic products obtained from algae

Algae (singular: alga) are plants or plantlike organisms that contain chlorophyll (pronounced KLOR-uh-fill) and other pigments (coloring matter) that trap light from the Sun. This light energy is then converted into food molecules in a process called photosynthesis. Most algae store energy as some form of carbohydrate (complex sugars).

Algae can be either single-celled or large, multicellular organisms. They can occur in freshwater or salt water (most seaweeds are algae) or on the surfaces of moist soil or rocks. The multicellular algae lack the true stems, leaves, or roots of the more complex,...