Q. Which of the following are correct according to operons?

i) Consists of multiple genes organized between a promoter and a terminator
ii) Member genes regulate with coordination
iii) Usually controlled by autogenous transcription
iv) Contains genes for stress tolerance exclusively

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Q. Choose the correct pair among the following.

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Q. Which of the following is not present in the β-galactosidase structural gene and thus is not transcribed by the same promoter?

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Q. Glucose, as the carbon source, is the first choice by bacteria even if other sugars are available. The mechanism behind this selectivity is ___________

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Q. The lac operon is regulated by cAMP by ___________

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Q. Tryptophan operon in E. coli is a repressible operon.

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Q. Which of the following is true about tryptophan operon?

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Q. The expression of the tryptophan operon is independent of the availability of tryptophan in culture media.

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Q. The functional unit in which genes are arranged consecutively is known as ___________

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Q. The investigation of the lac operon for the metabolism of lactose was done by __________

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Q. Presence of lactose itself induces the production of β-galactoside transferase.

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Q. How many enzymes are produced in the lac operon under the same promoter?

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Q. Defects in which regions can affect the activity of the lac operon?

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Q. If the lac operon of the genome of bacteria is always active it has a defect in which region of the operon?

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Q. Lac operon follows a trans-acting control mechanism.

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Q. According to the repressor of lac operon which of the following are false?

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Q. If there is an insertion mutation in the operator of the lac operon, the expression of the lac structural gene will be __________

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Q. The complete expression of the lac operon requires __________

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Q. What effect would a loss-of-function mutation have on the expression of the gene encoding the catabolite activator protein of the lac operon?

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Q. Mutation in the regulatory gene of a positively controlled operon can be identified by __________

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