Which of the following statement is correct about the reason that nucleic acid has the ability to absorb UV:____
A. The conjugated double bond between purine and pyrimidine
B. Ribose is connected to purine and pyrimidine
C. There are nitrogen atoms inside purine and pyrimidine
D. Ribose and phosphate is connected to purine and pyrimidine
E. Phosphate group is connected to purine and pyrimidine
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Which is the maximum UV absorption wavelength of nucleic acids:____
A. 280nm
B. 260nm
C. 240nm
D. 220nm
E. 490nm
Which of the following DNA molecule has a relatively higher Tm value?____
A. 5’-ATATCATATGATATGTA-3’
B. 5’-CGGTACTCGTGCAGGT-3’
The hybridization of nucleic acid could happen between DNA and RNA, DNA and DNA, then, which of the following RNA sequence could hybridize with single strand DNA with sequence 5’-CGGTA-3’:____
A. 5’-UACCG-3’
B. 5’-GCCAU-3’
C. 5’-GCCUU-3’
D. 5’-AUCCG-3’
E. 5’-UAGGC-3’
A circular DNA with B form reduces its crossing number by 1 with the help of topoisomerase I, then which the following is false:____
A. The linking number of this DNA is reduced by 1.
B. No ATP is consumed in this process.
C. This DNA can maintain its relaxed B form.
D. A negatively supercoiled DNA would be formed if it maintains its relaxed B form.
E. The twisting number of DNA would be keep the same if it maintains its relaxed B form.
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