举一反三
- Reverse transcriptase A: has 5ˊ → 3ˊ polymerase activity B: has 3ˊ → 5ˊ exonuclease activity C: is an RNA-dependent DNA polymerase D: is a DNA-dependent DNA polymerase
- DNA polymerase Ⅲ has a 5’→3’exonuclease activity A: 正确 B: 错误
- The 5'→3' exonuclease activity of intact DNA polymerase I can replace a segment of DNA (or RNA) paired to the template strand, in a process known as ____________________.
- Taq DNA polymerase had no 5 ′ → 3 ′ exonuclease activity.
- Which<br/>of the following are NOT true about DNA polymerase I in E.coli:() A: It<br/>can repair the gap in the single-strand DN B: It<br/>can replace DNA polymerase III to add dNTP into DNA chain when DNA<br/>template is damaged. C: It<br/>possesses activity of 3’→5’ exonuclease. D: Using<br/>dNTP as substrate. E: It<br/>possesses activity of 5’→3’ endonuclease.
内容
- 0
What is the function of RNA primer during DNA replication? A: to provide a 3’ OH group for DNA polymerase B: to provide a 5’ OH group for DNA polymerase C: to provide a 3’ phosphate group for DNA polymerase D: to provide a 5’ phosphate group for DNA polymerase E: to provide a hydrogen bond for double strand of DNA .
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E coli DNA polymerase III: A: can initiate replication without a primer. B: is efficient at nick translation. C: is the principal DNA polymerase in chromosomal DNA replication. D: represents over 90% of the DNA polymerase activity in E: requires a free 5'-hydroxyl group as a primer.
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Comparing<br/>DNA polymerase and RNA polymerase, the only differences is() A: The<br/>former has proof-reading activity, the latter doesn’t. B: The<br/>former requires primer, the latter doesn’t. C: The<br/>former can grow in both 5′→3′ and 3′→5′<br/>direction, the latter can only grow in 5′→3′. D: The<br/>former requires topoisomerase to relief stress, the latter doesn’t.
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Which of the following are NOT true about DNA polymerase I in E. coli: A: It can repair the gap in the single-strand DNA. B: It can replace DNA polymerase III to add dNTP into DNA chain when DNA template is damaged. C: Using dNTP as substrate. D: It possesses activity of 5’→3’ endonuclease.
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Enzymes participating in DNA replication include: (1) DNA polymerase III; (2) melting enzyme; (3) DNA polymerase I; (4) RNA polymerase (primerase); (5) DNA ligase . The order of action is: A: (2), (4), (1), (3), (5) B: (4), (3), (1), (2), (5) C: (2), (3), (4), (1), (5) D: (4), (2), (1), (5), (3) E: (4), (2), (1), (3), (5)