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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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In the complete absence of expression of lac operon, permease will not ve synthesised which is essential for transport of lactose from medium into the cells. And if lactose connot be transported into the cell, then it cannot act as inducers. Hence , cannot relieve the lac operon from its repressed state.
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