Let me share with you a comparison between Heterocyst and Hormogonia.
| Aspect | Heterocyst | Hormogonia |
| Function | Heterocysts are specialized cells that fix atmospheric nitrogen into a form usable by the cyanobacterium and neighboring cells. | Hormogonia are specialized filaments that function in the dispersal and colonization of new environments. |
| Structure | Larger in size as compared to vegetative cells. | Short, specialized filaments. |
| Cell Wall | Thicker cell wall to protect against oxygen. | Similar to the cell wall of vegetative cells. |
| Role in nitrogen fixation | Specialized for nitrogen fixation. | No role |
| Formation Regulation | Induced under nitrogen-limiting conditions. | Formed in response to environmental cues or stress conditions |
| Location | Distributed among vegetative cells in the filament. | Often found at the ends of filaments. |
| Role in filaments | Integral part of the filament structure. | May break away from the main filament to form new colonies or to colonize new areas. |