🧬 Biochemistry Solved MCQs with Answers

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

1490 solved MCQs

Which of the following is correct in terms of determination of location of genetic traits?Answer: Known protein coding sequences are too far apart to allow linkage determination for most new genes In gel electrophoresis, DNA molecules migrate from __________ to __________ ends of the gel.Answer: negative ... positive Restriction enzymesAnswer: All of the above First discovered, Type II restriction endonuclease wasAnswer: Hind II Which of the following techniques can be used to determine the defective gene and for developing cancer?Answer: Southern blot The transfer of antibiotic-resistant genes from genetically engineered bacteria to disease-causing bacteria __________ .Answer: Seems unlikely Both DNA gel electrophoresis and SDS-PAGE of proteins are similar becauseAnswer: All of the above Some genetic diseases cannot be diagnosed by changes in restriction sites. Some of these can be detected by allele-specific oligonucleotide probes. These areAnswer: Short sequences that will hybridize only to a specific base sequence In order to insert a foreign gene into a plasmid, both must __________Answer: Be cut by the same restriction enzyme Which of the following genetic diseases would be amenable to genetic engineering?Answer: Cystic fibrosis X-rays causeAnswer: Ionization of water in the cell The order for the construction of a cDNA fragment from mRNA is toAnswer: Bind oligo-dT, treat with reverse transcriptase, digest with RNase, add G residues to the 3' end, bind oligo-dC, treat with DNA polymerase The TP53 gene of chromosome 17 codes for a protein __________ .Answer: Involved in the regulation of the cell cycle Why is golden rice pale yellow in color?Answer: It is rich in beta-carotene. Which type of restriction enzymes do not usually require ATP?Answer: Type II An example of a restriction fragment length polymorphism isAnswer: Different length fragments of DNA resulting from loss or gain of a restriction site Knockout mice are created byAnswer: Transfecting embryonic stem cells with an altered gene sequence A plasmidAnswer: All of the above Under which of the following conditions would population gene frequencies remain the same?Answer: Random mating Plant transformation can be obtained byAnswer: Shooting DNA into plant cells with a gun An expression vectorAnswer: All of the above The unpaired nucleotides produced by the action of restriction enzymes are referred to haveAnswer: Sticky ends Which of the following is not true of small inbreeding populations?Answer: Mutation is increased Which of these genes codes for a protein that plays a role in growth?Answer: GH1 Which of the following pair will produce complementary sticky ends?Answer: Sau 3A & Bam HI A human cDNA libraryAnswer: Contains DNA for virtually all of the human proteins in vectors What enzyme forms covalent bonds between restriction fragments?Answer: DNA ligase Which of the following can be diagnosed by amniocentesis?Answer: All of the above Sex lethal (sxl) in Drosophila is transcribed whenAnswer: The X autosome balance is 1 or greater A mutation in the tip binding site of the repressor would result inAnswer: Constitutive trp operon expression