Answer :
Final answer:
Staphylococcus aureus grows on blood agar and belongs to option 3) Bacterial strain. It is a gram-positive bacterium with coccus morphology, and it is differentiated from other staphylococci by its ability to produce coagulase.
Explanation:
On blood agar, various types of bacteria can grow, including Staphylococcus aureus, which is the subject of your question. When Staphylococcus aureus is cultured on blood agar, it produces opaque white to cream colonies. This is indicative of a bacterial strain, not a fungal, pigmented, or non-pigmented strain. Thus, Staphylococcus aureus belongs to option 3) Bacterial strain. Moreover, this bacterium is characterized as gram-positive with a coccus (spherical) shape, often arranged in clusters resembling bunches of grapes.
Staphylococcus aureus is a member of the class Bacilli, and it is distinguished from other staphylococci by its ability to produce the enzyme coagulase. This characteristic enables clinicians to perform a coagulase test to identify this species when isolated from clinical specimens such as a skin infection wound swab.
