What term describes the structure that means to branch in bacteria?

The correct term that describes the structure meaning to branch in bacteria is "Filamentous." Filamentous bacteria are characterized by their long, thread-like structures that can branch out, resembling fine threads or filaments. This branching growth pattern can be seen in certain groups of bacteria, particularly in some species within the Actinobacteria phylum. These bacteria often form complex structures that can resemble mycelium, which is commonly associated with fungi.

The other terms refer to different bacterial shapes or arrangements. "Bacillus" refers to rod-shaped bacteria, "Spirillum" describes spiral-shaped bacteria, and "Coccus" pertains to spherical bacteria. While these terms define specific forms of bacterial morphology, they do not convey the characteristic of branching, which is why "Filamentous" is the appropriate choice for this question.