🧬 Biochemistry Solved MCQs with Answers

Practice 1490 approved 🧬 Biochemistry questions with verified answers from the 🧬 Medical Science subject for Pakistan exams.

1490 solved MCQs

The first protein complex to bind to the TATA box isAnswer: Transcription factor IID Which of the following is not part of the lac operon?Answer: I The lac operon is transcribed in which segments?Answer: 1 A frameshift mutation occurs in the sigma subunit gene transcribed as part of SPOl early genes. What will be the immediate result?Answer: The bacterial host will lyse immediately In the presence of high levels of tryptophanAnswer: Attenuator terminates transcription Tubulin is regulated byAnswer: Binding of tubulin to the tubulin translational product Transcription factors areAnswer: Proteins which bind DNAand initiate transcription Genes which need to be coordinately regulated but are not in operons may be regulated byAnswer: Common transcription factor binding domains What are genes?Answer: All of the above Which of the following is not a transcription factor?Answer: Steroid hormones Sex determination in Drosophila involvesAnswer: Alternate splicing Enhancers differ from promoters in thatAnswer: Their orientation can be inverted without effect Methylated gene areAnswer: Silent Which of the following occur in the presence of glucose?Answer: Binding of CAP-cAMP complex to the promoter area decreases Sex hormones activate transcription of specific genes byAnswer: Binding to a transcription factor The lac operon is translated into __________ proteins.Answer: 3 In the presence of tryptophan in the cell, the repressor is __________Answer: Bound to both DNA and tryptophan Catabolite activating protein exerts __________ control on transcription of the lac operon genes.Answer: Positive DNA is methylated atAnswer: CG sequences Why are several structural genes regulated as a unit in bacteria?Answer: It allows coordinating regulation of genes with a common function Alternate splicing of RNA transcripts is a mechanism to regulateAnswer: Tachykinins For gene transfer to be effective, transforming DNA must beAnswer: Incorporated into the bacterial chromosome Double stranded DNA denaturation with specified limit of temperature isAnswer: Reversible reaction From a single molecule of DNA, PCR can makeAnswer: Millions of copies Genomic libraries are made fromAnswer: Genomic DNA of an organism Bacteriophages areAnswer: Bacterial viruses Specialized transduction occurs whenAnswer: The bacteriophage always incorporates at the same position in the bacterial chromosome PCR is usedAnswer: All of the above To clone into a plasmid vector, both the plasmid and the foreign DNA are cutAnswer: With the same restriction enzyme and mixed together PCR can be used to amplify a specific fragment of DNA from which of the following?Answer: All of the above