The most common form of ultraviolet irradiation-induced DNA damage is the generation of thymine dimer. Which of the following statement is correct about changes of DNA structure in this process:()
A. It is the covalent linkage between thymines of the two complementary polynucleotide chain
B. It can be repaired by the relevant enzyme system including nucleotide excision repair system
C. It is catalyzed by thymine dimeric enzyme
D. It will not affect DNA replication process
查看答案
Single-base substitution is a kind of DNA damage, they can:()
A. affect transcription process instead of replication
B. affect DNA sequence but not DNA secondary structure
C. change DNA double helix structure but won’t affect replication process
D. be induced by ultraviolet irradiation(such as pyrimidine dimer)or the formation of additive compound (such as alkylation)
The damage of ultraviolet irradiation to DNA mainly is:()
A. Base substitution
Broken of phosphodiester bond
C. Deletion of base
D. Formation of covalent pyrimidine dimer
Which of the following belongs to spontaneous damage of DNA:()
A. Single-base mismatch during DNA replication
B. Formation of thymine dimer
Cytosine deoxidation
DNA cross-linking
The gap generated by hydrolysis of mismatch site in replication can be repaired by DNA polymerase I in E. coli.()
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