QBM Exam 3 Questions And Answers With Complete Solutions 2024

QBM Exam 3 Questions And Answers With Complete Solutions 2024 Which of the following DNA purification techniques CANNOT be used for genomic DNA purification? - answerminiprep Which DNA purification technique involves purifying the sample using an ultracentrifuge? - answerCesium chloride gradient What technique is used to increase plasmid copy number and purify plasmids? - answerMiniprep. Which of the following wavelengths is incorrectly matched? - answer240 nm - RNA concentration. The absorbance of a DNA sample at A260 = 1.0, and A280 = 1.0. Which of the following is TRUE? - answerThere is significant protein contamination of this sample RNA is more difficult to work with than DNA because - answerthe 2' hydroxyl group causes RNA to be more susceptible to degradation. Which of the following does NOT inhibit RNase activity? - answerEDTA An advantage of agarose gel electrophoresis over SDS-PAGE is that - answerALL (no stacking gel is needed, DNA can be purified and extracted, SDS is not required to maintain an equal charge-to-mass ratio, DNA can be loaded perpendicularly) The following DNA fragments are run on a gel. The DNA fragment in Lane 4 below is - answer600 bp Ethidium bromide is frequently chosen to visualize DNA on a gel because - answerIt is more sensitive than SYBR Green and crystal violet If Lane 1 contains undigested plasmid DNA and Lane 2 contains the same digested DNA sample, which of the following is TRUE about the gel below? - answerThe DNA sample has a molecular weight of 4 kb. Which of the following techniques is most appropriate for separating DNA fragments (>50 kb) for genotyping? - answerPulse-field gel electrophoresis. What is the most sensitive DNA visualization method? - answerAutoradiography. Which of the following is a downstream application of agarose gel electrophoresis? - answer(ALL) DNA sequencing, Southern blotting for DNA samples, northern for RNA sample To extract DNA from a gel you would perform a - answergel extraction and freeze squeeze A collection of cells that are all descendants from the same cell are called - answerclones Which of the following is NOT a tool used in recombinant DNA technology? - answerUsing primase to catalyze the formation of phosphodiester bonds. Which of the following is TRUE about restriction enzymes? - answerThey generally recognize palindromic DNA An E. coli genomic DNA fragment is run out on a gel undigested (U), and then with two different restriction enzymes. Based on the gel below, what is the most appropriate reason for the band pattern displayed? - answerThe DNA fragment is methylated at the EcoRI cut site, but not the DpnI cut site Which is TRUE regarding EcoRI, which cuts at GAATTC? - answerIt is naturally found in E. coli. What is true about the following enzymes? SmaI - CCC^GGG XmaI - C^CCGGG - answerThey are neoschizomers. Based on the restriction enzyme table below, which of the following is TRUE? - answerXbal and BamHI should ideally be used together in Buffer 2 Three samples are digested with EcoRI and run out on a gel as shown. What can be done to prevent the star activity seen in Lane 4? - answerAll (Maintain a lower DNA enzyme ratio, adjust the pH of the buffer to ensure optimal conditions for the restriction enzyme, remove glycerol and ethylene glycol from the buffer, remove glycerol and ethylene glycol from the buffer, use a high-fidelity enzyme to reduce star activity) Based on the following restriction digests with restriction enzymes A and B, what could be a possible restriction map that fits this data? The lines in the answers represent a single piece of DNA, and the As and Bs represent cut sites. - answerNOT AABB OR A B OR A A A B TRY AAAB A circular piece of DNA is cut with HpaII and generates 3 fragments. How many HpaII cut sites were present on the circular DNA? - answer3 Which lane below represents a dige