Tag: dbt jrf 2018

69. Which of the following amino acid changes in the active site of an enzyme is most likely to change its activity? 1. Lys → Arg 2. Leu → Ile […]

68. Which of the following statements about IPTG and lactose is NOT correct? 1. IPTG is an analog of lactose 2. Both IPTG and lactose are inducers of the lac […]

67. A Yeast plasmid vector has an XhoI site in the LEU2 marker gene and a SalI site in the HIS3 marker gene. A student cloned a gene using the […]

65. A DNA fragment digested with HindIII and EcoRI was ligated with a vector digested with HindIII and EcoRI sites present in the polylinker of the vector. Upon screening of […]

64. A Bacillus culture growing in a rich medium was shifted to a sporulation medium. Which of the following is expected to occur? 1. Genome and transcriptome will change 2. […]

63. Termination of mRNA transcription in Saccharomyces cerevisiae is mediated by: 1. Rho-dependent termination 2. Rho-independent termination 3. Polyadenylation signal 4. Sigma factor directed termination Introduction In Saccharomyces cerevisiae, a […]

62. Among the merodiploids of the lac operon in E. coli, which one is NOT inducible by lactose? 1. i – p o z/ i p o z 2. i […]

61. In a cell, a repressor binds to its cognate operator with a KD = 10-9M. The cellular concentration of the repressor is 10-8M. The extent of repressor bound to […]

60. A linear double stranded DNA is self-circularized by ligation with T4 DNA ligase. At which concentration (μg/ml) of DNA would the self-circularization yield be maximum? 1. 30 2. 10 […]

59. Aminopterin in HAT medium inhibits: 1. Thymidine kinase 2. Hypoxanthine – guanine phosphoribosyltransferase 3. Ribonucleotidereductase 4. Dihydrofolatereductase Aminopterin in HAT Medium: Inhibiting DNA Synthesis for Hybridoma Selection In the […]