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Biology · 2025 · 3 marks
CBSE 2025 · Region 6 · Set 1 · Q25
Explain how the addition of lactose in the medium regulates the switching on of the lac operon in bacteria.
Explain how the addition of lactose in the medium regulates the switching on of the lac operon in bacteria.
Marking-scheme solution
Lactose transported into the cell through permease, in the presence of an inducer lactose the repressor is inactivated by interaction with the inducer, this allows RNA polymerase access to the promoter and transcription proceeds
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