1. Both strands of DNA serve as templates concurrently in
A.replication
B.excision repair
C.mismatch repair
D.none of these

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2. Both strands of DNA serve as templates concurrently in
A.replication
B.excision repair
C.mismatch repair
D.none of these

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3. Proofreading activity to maintain the fidelity of DNA synthesis
A.occurs after the synthesis has been completed
B.is a function of the 3'-5' exonuclease activity of the DNA polymerases
C.requires the presence of an enzyme separate from the DNA polymerases
D.occurs in prokaryotes but not eukaryotes

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4. Which of the following repairs nicked DNA by forming a phosphodiester bond between adjacent nucleotides?
A.Helicase
B.DNA gyrase
C.Topoisomerases
D.DNA ligase

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5. The enzyme that catalyzes the synthesis of DNA is called
A.DNA polymerase
B.DNA gyrase
C.DNA ligase
D.helicase

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6. Which of the following possesses both 5'-3' and 3'-5' exonuclease activity?
A.Kornberg enzyme
B.DNA polymerase III
C.Taq DNA polymerase
D.None of these

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7. Which of the following statements on replication in E.coli is correct?
A.It occurs in a unidirectional manner
B.It occurs in bidirectional manner
C.Always uses T7 DNA polymerase when infected by T7 phage
D.Occurs only when λ phase has infected E. coli

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