If Escherichia coli is cultured in broth containing both glucose and lactose,it

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E. coli prefers glucose as its primary energy source and will utilize it until the supply is exhausted, then it will switch to lactose. This is due to the fact that the genes for glucose metabolism are constitutively expressed while the genes for lactose metabolism are inducible and only expressed when lactose is present. There is also a phenomenon called catabolite repression where glucose inhibits the expression of the lactose metabolism genes even when lactose is present, which further supports the idea that E. coli will use glucose preferentially.

If Escherichia Coli Is Cultured in Broth Containing Both Glucose