DNA replication requires: (1) DNA polymerase III, (2) helicase, (3) DNA polymerase I, (4) DNA-directed RNA polymerase, (5) DNA ligase, the correct order of their participation is:()
A. 4,3,1,2,5
B. 2,3,4,1,5
C. 4,2,1,5,3
D. 4,2,1,3,5
E. 2,4,1,3,5
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The enzyme catalyzing the formation of phosphodiester bond between 5’phosphate group and the 3’hydroxyl in DNA is: ()
A. methyltransferase
B. ligase
C. primase
DNA pol I
E. terminal transferase
The wrong statement about the semi-discontinuous synthesis of DNA is:()
A. Leading strand is synthesized continuously
B. Lagging strand is synthesized discontinuously
C. The discontinuously synthetic fragments are Okazaki fragments
D. Half of the leading strand as well as half of the lagging strand is discontinuously synthesized
E. Synthesis of lagging strand is later than the leading strand
The function of DNA topoisomerase is:()
A. Identifying the origin of replication
B. Straightening out the DNA strand during replication
C. Stabling DNA molecule topological conformation
D. Opening the hydrogen bond between the DNA double helix
E. Making DNA molecule become positive supercoiled
Which of the following statement about the role of helicase in DNA replication is NOT true:()
A. to open hydrogen bond between the base pair
B. will consume ATP to provide energy
C. It will bind to the DNA double helix
D. Its activity is activated by DNA replication complex
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