bacterial morphology and diversity:
Bacteria are unique and diverse and come in a variety of different shapes (morphologies) and arrangements. This is very important in aiding in the identification of the bacteria.
Cell Shapes:
Cell Shapes:
- Cocci (round) or coccus (singular)
- Bacilli (rods) or bacillus (singular)
- Spirilla (spiral) or spirillum (singular)
- Vibrios (slightly curved rods like commas)
- Coccobacilli (short rods/oval shape)
- Spirochetes (flexible spirals)
- Pleomorphism (a variety of cell shapes)
- Single cells
- Diplococci (cocci in pairs): this means that the 2 daughter cells remained attached after the coccus divided
- Streptococci (cocci in chains: this means that the cells continued to divide in the same plane and remained attached
- Staphylococci (cocci in clusters)
- Tetrads (cocci in packets of 4): this means that a cellular division has occurred and it is the 2nd division occurring in a plane perpendicular to the 1st
- Sarconae (cocci in packets of 8): this means that another cellular division has occurred and it is the 3rd division perpendicular to the other 2, producing a cube-shaped arrangement
- Diplobacilli (rods in pairs): this means that the 2 daughter cells remained attached after the bacillus divided
- Streptobacilli (rods in chains): this means that the cells continued to divide in the same plane and remained attached
- Palisade (rods side-by-side)
- Coryneform ("Chinese letters")
- Actinobacteria/Actinomyces (branching rods)
- Mycobacterium (cords): grow in parallel chains
- Fusiform (pointed or narrowed at the ends)
cocci: Round-to-oval spheres
diplococci: spheres in pairs (Typically lancet-shaped or kidney bean shaped
Neisseria gonorrhoeae are Gram-negative diplococci (pairs) shaped like kidney beans or coffee beans facing each other.By CDC/ Joe Millar - This media comes from the Centers for Disease Control and Prevention's Public Health Image Library (PHIL), with identification number #4085.Note: Not all PHIL images are public domain; be sure to check copyright status and credit authors and content providers.English | Slovenščina | +/−, Public Domain, https://commons.wikimedia.org/w/index.php?curid=722357
streptococci: spheres in chains
Staphylococci: spheres in grape-like clusters
Staphylococci are bacteria in grape-like clusters;By CNX OpenStax - https://cnx.org/contents/[email protected], CC BY 4.0, https://commons.wikimedia.org/w/index.php?curid=53713001
tetrads and sarcinae: spheres in packets of four or eight
bacilli: (ALso called "rods"): thick, thin, or filamentous, some are branching, some produce endospores; some are short, some are long
This image of Lactobacilli is a great example of bacilli in singles, pairs, chains, and palisade formation;By Photo Credit: Janice CarrContent Providers(s): CDC/Dr. Mike Miller - This media comes from the Centers for Disease Control and Prevention's Public Health Image Library (PHIL), with identification number #1048.Note: Not all PHIL images are public domain; be sure to check copyright status and credit authors and content providers.English | Slovenščina | +/−, Public Domain, https://commons.wikimedia.org/w/index.php?curid=640855