Cocci are described as which of the following?

Cocci are described as which of the following?

• A. Rod-shaped bacteria
• B. Round shaped bacteria that appear alone or in groups: staphylococci, streptococci, and diplococci
• C. Pus forming bacteria
• D. Spiral-shaped bacteria

Answer: (B)

Cocci are spherical bacteria. They can be seen alone or in characteristic groupings: grape-like clusters (staphylococci), chains (streptococci), or pairs (diplococci). The other descriptors refer to different shapes—rod-shaped bacteria are bacilli, spiral-shaped bacteria are spirilla or spirochetes—and “pus-forming” isn’t a shape classification. So describing cocci as round-shaped bacteria that appear alone or in groups such as staphylococci, streptococci, and diplococci best captures what cocci are.

Cocci are spherical bacteria. They can be seen alone or in characteristic groupings: grape-like clusters (staphylococci), chains (streptococci), or pairs (diplococci). The other descriptors refer to different shapes—rod-shaped bacteria are bacilli, spiral-shaped bacteria are spirilla or spirochetes—and “pus-forming” isn’t a shape classification. So describing cocci as round-shaped bacteria that appear alone or in groups such as staphylococci, streptococci, and diplococci best captures what cocci are.