Bio A2 Help?

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    explain what will happen when E.coli is grown on a growth medium containing with glucose and lactose(4 marks)

    I haven't studied this but a quick google search tells me that what you could be referring to is Carbon catabolite repression. This occurs when a micro-organism such as E.coli has access to more than one nutrient source (such as the presence of glucose and lactose) and this allows the bacterium to adapt quickly to a preferred and rapidly metabolisable energy source first. So when E.coli is grown in a growth medium containing both glucose and lactose, it will use glucose first as it grows faster on glucose than any other carbon source. Thus, lactose is said to be subjected to catabolite repression and this delays the synthesis of galactosidase which would otherwise have been synthesised first if glucose had not been present in the growth medium. Here's the link:

    Hope this helps

    Haven't studied either, but I think the E.coli metabolises the glucose, then something to do with the lac operon, so it then can metabolise the lactose
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