Question Detail

MIC 121 Mcb compilations Objective Question

Question

What makes chocolate agar an enriched medium?
Options
A It includes selective agents to inhibit unwanted bacteria
B It has a high salt concentration
C It contains glucose as a carbon source
D It contains heat-treated blood, giving it a brown color
Correct Answer
Correct Answer

Option D is the correct answer.

Detailed Explanation

Chocolate agar is an enriched medium made by heating blood (typically sheep's blood) to lyse red blood cells, releasing factors like hemin (X factor) and NAD (V factor) into the agar, which are essential nutrients for fastidious bacteria like Haemophilus and Neisseria species. This heat treatment gives it a characteristic brown 'chocolate' color.

Hint

Think about the key ingredient in chocolate agar and how it's treated to release essential growth factors.

Question Info