Eosin methylene blue agar (EMB) is a selective and differential medium. The dyes in the medium inhibit most Gram-positive organisms. Gram-negative organisms such as the coliforms grow on this medium. Coliforms that are fecal in origin produce colonies with a metallic green color on EMB, while those that are non-fecal produce colorless colonies. You plate a urine sample onto an EMB plate and incubate it. Metallic green colonies develop. From this, you can conclude that
A) the sample contains bacteria that are Gram-negative AND are non-fecal in origin.
B) the sample contains bacteria that are Gram-negative AND are fecal in origin.
C) the sample contains bacteria that are Gram-positive AND are fecal in origin.
D) the bacteria in the colonies are Gram-positive AND are rod-shaped.
E) normal microbiota in the bladder is fecal in origin AND is aerobic.

Question

Eosin methylene blue agar (EMB) is a selective and differential medium. The dyes in the medium inhibit most Gram-positive organisms. Gram-negative organisms such as the coliforms grow on this medium. Coliforms that are fecal in origin produce colonies with a metallic green color on EMB, while those that are non-fecal produce colorless colonies. You plate a urine sample onto an EMB plate and incubate it. Metallic green colonies develop. From this, you can conclude that 
A) the sample contains bacteria that are Gram-negative AND are non-fecal in origin.
B) the sample contains bacteria that are Gram-negative AND are fecal in origin.
C) the sample contains bacteria that are Gram-positive AND are fecal in origin.
D) the bacteria in the colonies are Gram-positive AND are rod-shaped.
E) normal microbiota in the bladder is fecal in origin AND is aerobic.

Quizplus · Accepted Answer

The metallic green colonies on EMB indicate the presence of Gram-negative bacteria that are fecal in origin.

Eosin Methylene Blue Agar (EMB) Is a Selective and Differential