The correct option is 2: Nostoc Nostoc is an example of a cyanobacterium, which is a type of photosynthetic prokaryote that is often colloquially referred to as blue-green algae. This organism possesses a unique and vital metabolic capability known as atmospheric nitrogen fixation. Nitrogen fixation is the complex biochemical process of converting inert, gaseous nitrogen (N2) from the atmosphere into a biologically usable form, primarily ammonia (NH3), which can then…Read More