Photosynthesis is the process that converts energy from sunlight into chemical forms of energy that can be used by biological systems. The best known form of photosynthesis is carried out by higher plants and algae as well as cyanobacteria and their relatives. They convert carbon dioxide to organic material by reducing this gas to carbohydrates.
Cyanobacteria combine the fixation of carbon dioxide and nitrogen. As such, they contribute greatly to the global nitrogen budget. Algae are rather diverse, and their only common feature is the production of aerobic photosynthesis.Learn more about Biology