Anabaena is a genus of filamentous cyanobacteria that reside as plankton.
They are known for their nitrogen-fixing abilities, and they create symbiotic partnerships with specific plants, such as the mosquito fern.
They are one of four cyanobacteria genera with neurotoxins that are harmful to domestic animals, farm animals, and pets in the area.
Its cells resemble beads or barrels and have interspersed elongated spores (heterocysts).
The vegetative cell known as Anabaena forms long filaments.
One in ten cells has the ability to divide into a heterocyst when the system lacks nitrogen.
Due to the need of keeping nitrogenase apart from oxygen, heterocysts have evolved components to maintain a low quantity of oxygen within the cell.
In order to block oxygen from entering the cell, the growing heterocyst grows three extra layers outside of the cell wall, giving it a unique enlarged and rounded look.