In Cyanobacteria, All these structures are present except:

Explanation

Cyanobacteria are a group of photosynthetic bacteria that possess various structures and forms. Some common structures found in cyanobacteria include: Filaments: Cyanobacteria often form filamentous structures, where individual cells are connected in a chain-like arrangement. These filaments can be unicellular or multicellular. Unicellular Forms: Some cyanobacteria exist as individual cells or colonies of cells that do not form filaments. Heterocysts: Certain cyanobacteria possess specialized cells called heterocysts. Heterocysts are involved in nitrogen fixation, converting atmospheric nitrogen into a form that can be utilized by the organism. Sheaths: Cyanobacteria may secrete protective sheaths around their filaments. These sheaths provide structural support and protection. However, a "jelly-like mass" is not a typical characteristic of cyanobacteria. Cyanobacteria are primarily characterized by their filamentous or unicellular forms, along with the presence of specialized structures like heterocysts and sheaths.