Algae are organisms bearing chlorophyll, they are simple, thalloid, atutotrophic and mostly aquatic organisms. They are both fresh water and marine organisms. They occur in a variety of habitats and also in association with fungi as animals. They are of variable sizes, they may be microscopic like Chlamydomonas
and colonial forms like Volvox
, few marine forms like kelps form massive plant bodies. Reproduction in algae is by vegetative, asexual and sexual methods.
Algae are useful in many ways:
- They can fix carbon dioxide through photosynthesis.
- They increase the level of dissolved oxygen in their immediate environment.
- They are important as they are primary producers which form basis of the food cycle of all aquatic organisms.