Structural Categories of Bacteria and their Shapes essay

StructuralCategories of Bacteria and their Shapes

Thecocci bacteria cells are round-shaped but sometimes they can be flatwhen they are close to one another. Some other types of the cocci areelongated. These bacteria are found in different forms, and the mostcommon are the diplococci, tetrads, streptococci, staphylococci, andsarcinae. The diplococci remain in pairs whereas the streptococciappear in chains after dividing. The tetrad divides into two planesthat make them stay four of them in each group. The sarcinaetypically divides into three planes and the groups formed looks likecubes having eight cocci each. Lastly, there are cases where thedivision takes multiple planes and forms cocci that look likeclusters of grapes. This category is known as staphylococci. Thedifferent types of cocci can only be clearly identified after thecell division has taken place for them to make the different shapes.The staph aureus is one of the cocci bacteria that cause thepneumonia disorder among most people.

TheBacilli takes the form of a rod. These bacteria can as well be foundin different forms. There are the diplobacilli that that takes theshape of a single rod or two rods in case of diplobacilli. Anothercategory is the Streptobacilli that appear in chains whereas thecoccobacilli are very short and stumpy and when observed they appearovoid. Lastly, the Palisades form bends at the point where theydivide during the cell division. The Bacilli bacteria like theCorynebacterium causes diphtheria disease that makes it difficult forthe patient to breathe or swallow.

Finally,spirilla are curved while others are corkscrew-like resembling thespiral. Their structure is like a rigid spiral and in cases wherethey have several turns they look like a spirochete. The spirillabacteria specifically the Campylobacter jejuni causes the stomachinflammation and the ulcers.


Aryal,S. (2015). DifferentSize, Shape and Arrangement of Bacterial Cells,Retrieved from May 28, 2016.