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A-LevelBiologyNucleic acids and protein synthesisMay/June 2022Paper 4 Q79 Marks

The bacterium, Escherichia coli, can use glucose or disaccharides, such as lactose, in its metabolism. Lactose needs to be hydrolysed by the enzyme β-galactosidase to form glucose and galactose, which can then be used by E. coli. The production of β-galactosidase is controlled by a length of DNA called the lac operon.

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About This A-Level Biology Question

This structured question appeared in the Cambridge A-Level Biology (9700) May/June 2022 examination, Paper 4 Variant 2. It tests the topic of Nucleic acids and protein synthesis and is worth 9 marks.

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