What are main characteristic feature of algae?

• Algae are eukaryotic organisms.
• They do not have any leaves, roots or stems.
• Green algae have chlorophyll with the help of which they perform photosynthesis.
• They may be unicellular or multicellular.
• They usually grow in water or in humid, moist and shady places.

E.g. chlorella, spirogyra, nostoc, kelp etc.