Question

are any of these colonies recognizable?

Nutrent Coco
nutrient agar

mac conkeys agar

tomato juice agar

they all gram stained negative.

Answer 1

ANS : According to the above shown culutre ,there are three culutre medium:-

1.nutrients agar medium

2. Macconkey agar medium

3. tomato juice agar medium

and only bacterial negative stain colony grown.

SO,answer is gram negative stain bacteria colony grow only in MacConkey agar a bacterial growth medium that is selective for Gram -negative bacteria and differential for enetric baclli that ferment lactose.

Its used to identify the bacteria Kiebsiella pneumoniae,E.coli, Salmonella typhimurium

THIS medium contain crystal violet and bile salts to inhibit the growth of Gram +bacteria.

medium Agar nutrients medium is the commonly used medium for yhe microbial studies and tonly common bacteria can grown on it that are nonfastidious.

Tomato juice donot provide the suitable growth for the Gram -negative bacteria. dueto its acidic nature