Question

In emb agar, _________ is(are) selective agent and ________ is a differential agent. crystal violet, lactose eosin, methylene blue eosin and methylene blue, lactose lactose, eosin and methylene blue

Answer 1

In EMB agar, crystal violet is a selective agent and lactose, eosin, and methylene blue are differential agents.

Step-by-step explanation:

In EMB agar, crystal violet is a selective agent and lactose, eosin, and methylene blue are differential agents.

EMB agar is a medium used to identify and isolate pathogenic bacteria. It contains digested meat proteins as a source of nutrients. The selective agent, crystal violet, inhibits the growth of gram-positive bacteria. The differential agents, lactose, eosin, and methylene blue, help distinguish between lactose fermenting and nonlactose fermenting organisms.

Answer 2

On EMB agar, eosin and methylene blue are the selective agents and lactose is the differential agent.

Step-by-step explanation:

In EMB agar, eosin and methylene blue are selective agents that inhibit the growth of gram-positive bacteria, and lactose is the differential agent that distinguishes between lactose fermenting and non-lactose fermenting organisms. Bile salts and crystal violet also act as selective agents for certain other media like MacConkey agar, which is not the case for EMB agar. Instead, EMB agar focuses on using its dyes to suppress the growth of certain bacteria while the presence of lactose allows for the differentiation of colonies based on their fermentation abilities.