Gram-positive Cocci

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Gram-positive Cocci

Bacteria may have a very distinctive appearance when viewed on a Gram stained smear. Distinct characteristics are not as evident on direct smears as they are on Gram stains of colonies and/or stains from broth cultures, but these shapes can be identified on direct smears.
  • Cocci: Round or oval
  • Bacilli: Rod-shaped
Gram-positive cocci (GPC):
  • Singly and in clusters (May indicate staphylococci)
  • In pairs and chains (May indicate streptococci)
GPC can be seen in clusters and chains in Image 1 below.

Image 1. Gram-positive cocci in clusters and chains.