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A low level of expression of lac operon ...

A low level of expression of lac operon occurs at all the time. Can you explain the logic behind this phenomena.

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Enzyme permease is essential for the transport of lactose from outside into the cells. This enzyme is synthesised by one of the genes of lac operon system. In case, lac. operon stops functioning completely, no permease will be synthesised and transport of lactose into the cell will stop. Lactose functions as inducer for lac operon. In absence of lactose transport into the cell, the lac operon will not be induced and cell will. fail to utilise lactose for metabolism
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