Question

Define the following terms: Selective media Differential media Enrichment media Selective differential media

Answer 1

Selective media

Selective media allows the growth and development of certain sort of organisms,, while restraining the development of other organisms.

This selectivity is accomplished in a few ways. For instance, living beings that can use a given sugar are screened effectively by making that specific sugar the main carbon source in the medium for the development of the microorganism. Like-wise, the particular hindrance of a few sorts of microorganisms can be contemplated by including certain colors, anti-microbials, salts or particular inhibitors that will influence the digestion or enzymatic frameworks of the living beings.

For instance, media containing potassium tellurite, sodium azide or thallium acetic acid derivation at various centralizations of 0.1 - 0.5 g/l will hinder the development of all Gram-negative microscopic organisms. Media supplemented with the anti-toxin penicillin fixation 5-50 units/ml or precious stone violet 2 mg/l restrain the development of Gram-positive microscopic organisms.

Tellurite agar, is utilized to choose for Gram-positive living beings, and supplement agar supplemented with the anti-toxin penicillin can be utilized to choose for the development of Gram negative life forms.

Eg., Mannitol salt agar, Hektoen enteric agar (HE), Phenylethyl liquor agar

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Differential media

Differential media are broadly utilized for separating firmly related organisms or gatherings of organisms. In view of the nearness of specific colors or chemicals in the media, the living beings will deliver certain trademark changes or development designs that are utilized for recognizable proof or separation of microorganism.

Eg., Mac Conkey (MCK) agar, Eosin Methylene Blue (EMB) agar

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Enrichment media

It will be media that have been supplemented with very nutritious materials, for example, blood, serum or yeast remove with the end goal of developing demanding creatures.

Eg., Blood agar, Chocolate agar

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Selective- differential media:

are utilized to detach or distinguish specific life forms.

Specific media permit certain sorts of living beings to develop, and hinder the development of different life forms.

The selectivity is refined in a few ways.

For instance, life forms that can use a given sugar are effortlessly screened by making that sugar the main carbon source in the medium.

Then again, specific hindrance of a few sorts of microorganisms can be accomplished by including colors, anti-microbials, salts or particular inhibitors which influence the digestion or chemical frameworks of the life forms.

For instance, media containing potassium tellurite, sodium azide or thallium acetic acid derivation (at convergences of 0.1 - 0.5 g/l) will hinder the development of Gram-negative microscopic organisms