What is the waste gas produced by cyanobacteria?

The waste gas produced by cyanobacteria is primarily oxygen (O₂). During the process of photosynthesis, cyanobacteria convert carbon dioxide and sunlight into energy, releasing oxygen as a byproduct. This oxygen production significantly contributes to the Earth's atmosphere and supports aerobic life forms. Additionally, some cyanobacteria can produce trace amounts of other gases, such as nitrogen oxides, under certain conditions.