Heterocyst of Nostoc Structure and Function

Nostoc is a Colonial, filamentous algae seen as mucilaginous balls that belongs to the class cyanophyceae (Blue green algae)

•    Heterocysts are Large sized, colourless, spherical, thick walled cells present in the filaments of blue green algae like Nostoc

•     Position intercalary or terminal

•    A prominent granule is present at each pole of the heterocyst called polar nodule.

Functions

-Main site of Nitrogen fixation

-Helps in vegetative reproduction; function as “point of breakage” of filaments; sometimes germinate into new filament

-Stimulate production of akinetes

-Serves as storage organs
More on Nostoc: Nostoc Taxonomic position, Habitat and Cell structure
                           Reproduction in Nostoc