Bacteria that ferment lactose grow as red colonies on MacConkey agar while those that do not ferment lactose are pink. MacConkey agar can best be described as being
A) selective
B) differential
C) complex
D) enriched

Question

Quizplus · Accepted Answer

MacConkey agar is a differential medium, which means it can distinguish between different types of bacteria based on their ability to ferment lactose. It also contains bile salts and crystal violet, which inhibit the growth of Gram-positive bacteria and make the medium selective for Gram-negative bacteria. Additionally, MacConkey agar is a simple medium, consisting of only a few ingredients.

Bacteria That Ferment Lactose Grow as Red Colonies on MacConkey