Staphylococcus is a genus of Gram-positive bacteria in the family Staphylococcaceae from the order Bacillales. Under the microscope, they appear spherical (cocci), and form in grape-like clusters. Staphylococcus species are facultative anaerobic organisms.
Staphylococcus
Unknown variety of Staphylococcus, Gram-stained – numbered ticks on the scale are 11 µm apart
In bacteriology, gram-positive bacteria are bacteria that give a positive result in the Gram stain test, which is traditionally used to quickly classify bacteria into two broad categories according to their type of cell wall.
Rod-shaped gram-positive Bacillus anthracis bacteria in a cerebrospinal fluid sample stand out from round white blood cells, which also accept the crystal violet stain.
Violet-stained gram-positive cocci and pink-stained gram-negative bacilli
Colonies of a gram-positive pathogen of the oral cavity, Actinomyces sp.