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’
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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.
Which the following is correct about the topoisomerase II:____
A. It can break the glycosidic bond in DNA double strands.
B. It doesn’t consume ATP when it works.
C. It can increase the number of negatively supercoiled DNA.
D. It can stabilize the topological structure of DNA molecule.
E. It makes positive supercoiled DNA.
Which the following is false about the supercoil structure of DNA:____
A. It’s the character of closed circular DNA (Once a single strand or double strands break, the supercoil of DNA is destroyed)
B. Topoisomerases in the cell can regulate the level of supercoil of DNA.
C. The formation of DNA supercoil needs DNA ligase.
D. Almost all DNA molecules in the cell is negatively supercoiled.
E. The level of supercoil of DNA is regulated by topoisomerases.
Which the following is false about the tertiary structure of DNA:____
A. Kink of the chain
B. Supercoil
C. Loops formed within a single strand of DNA
D. Concatenated circle in circular DNA
E. Double helix of DNA
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