A mutation in the regulatory gene of the lac operon may result in
A - VCE - SSCE Biology - Question 3 - 2017 - Paper 1
Question 3
A mutation in the regulatory gene of the lac operon may result in
A. inhibition of the operator gene.
B. RNA polymerase not being able to perform transcription.
C. t... show full transcript
Worked Solution & Example Answer:A mutation in the regulatory gene of the lac operon may result in
A - VCE - SSCE Biology - Question 3 - 2017 - Paper 1
Step 1
A. inhibition of the operator gene.
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Answer
This statement is incorrect. A mutation in the regulatory gene does not necessarily lead to inhibition of the operator gene.
Step 2
B. RNA polymerase not being able to perform transcription.
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Answer
This is also incorrect. A mutation in the regulatory gene does not directly prevent RNA polymerase from performing transcription; it affects the operon's regulation mechanism.
Step 3
C. the lac operon switching on in the presence of lactose only.
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Answer
This statement is misleading. The lac operon is designed to switch on in the presence of lactose, but a mutation in the regulatory gene could alter this behavior, leading to potential activation even without lactose.
Step 4
D. production of a repressor molecule that is unable to bind to the operator gene.
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Answer
This statement is correct. A mutation in the regulatory gene can lead to the production of a repressor molecule that is unable to bind to the operator gene, resulting in the constitutive expression of the operon.
