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Name: Fio
Status: Student
Age: 15
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Date: N/A 

Why are peptone and beef extract needed in culture mediums? what procedures are done in the culture of lactobacilli

There are two types of media for the growth of organisms. One is called defined media; this is when every ingredient in the media is known in the exact proportions. This is kind of like using a recipe with all the ingredients measured out exactly. The second kind is called complete media. This is where although the exact proportions are not known, it seems to provide everything the bacteria need because they grow vigorously on it whenever it is used. Peptone and beef extract are known to be very nutritious to bacteria and most types of bacteria grow very well on it.


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