Tampons shouldn't be worn overnight because... 1  Tampons need to be changed every 4-6 hours and many people sleep longer than this - changing often is important as tampons allow bacterial growth while preventing vaginal cleaning so the longer a tampon is worn the more bacteria can multiply within the vagina.
MacConkey agar is a selective medium containing bile salts and crystal violet that inhibits the growth of Gram-positive bacteria while allowing for the growth of Gram-negative bacteria.MacConkey agar is often used when investigating and culturing fecal bacteria.he MacConkey agar we talked about as an example of a selective media is also a differential media. In addition to the selective bile salts and crystal violet, MacConkey agar contains a pH indicator and the sugar lactose.
Media are used to grow bacterial colonies (millions of bacteria having arisen through the binary fission of a single progenitor). Article Summary: Blood Agar is a bacterial growth medium that can distinguish normal from pathogenic bacteria based on the effect of bacterial hemolytic exotoxins on red blood cells.Blood Agar (BAP) Bacterial Growth Medium.f a bacterial growth medium is selective, that means that it grows only certain types of microbes while inhibiting the growth of other types of microbes. Blood agar is an enriched medium that provides an extra rich nutrient environment for microbes.