NURSING EXAM QUESTIONS
MICROBIOLOGY
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Question
[CLICK ON ANY CHOICE TO KNOW THE RIGHT ANSWER]
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A laboratory technician uses a MacConkey agar that is designed to suppress the growth of Gram-positive bacteria, and encourage the growth of Gram-negative microbes. MacConkey agar is a type of ____
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differential media
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selective media
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nutrient agar
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nutritive media
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Explanation:
Detailed explanation-1: -Selective media are designed to suppress the growth of unwanted bacteria and encourage the growth of the desired microbes. For example, bismuth sulphite agar (BSA) is one medium used to isolate the typhoid bacterium, the gram-negative Salmonellatyphi, from faeces.
Detailed explanation-2: -MacConkey agar is an example of a medium that is both differential and selective. The presence of bile salts, as well as crystal violet, within the media prevent gram-positive organisms from growing.
There is 1 question to complete.