Question

A nasopharyngeal swab from a young woman is plated on a selective agar medium. What is the function of plating this sample on a selective medium?

Choose one:
A. The selective medium will eliminate or reduce the number of normal microbiota.
B. The selective medium will allow only suspected pathogens to grow.
C. The selective medium allows growth of pathogens in only part of the agar plate.
D. The selective medium contains dyes that change color in the presence of pathogens.

Answer 1

Plating the nasopharyngeal swab on a selective medium eliminates or reduces normal microbiota and allows suspected pathogens to grow.

Step-by-step explanation:

The function of plating a nasopharyngeal swab from a young woman on a selective medium is to eliminate or reduce the number of normal microbiota and allow only suspected pathogens to grow.

Selective media contain substances such as bile salts and dyes that inhibit the growth of unwanted microorganisms and favor the growth of specific pathogens. By using a selective medium, we can create an environment that is conducive to the growth of the bacteria we are interested in and suppress the growth of other bacteria. This helps in isolating and identifying the suspected pathogens present in the sample.