DNA replication in eukaryotes（）
A. usually starts at the same place every time
B. only involve 2 different DNA polymerases
C. is faster than in bacterial DNA replication
D. all of the above are false
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Transposition（）
Also requires homology between sequences
B. Occurs only in prokaryotes
C. Was firstly discovered by Sanger
D. Needs transposase to catalyzes the insertion
The methylation of GATC sequences in E. coli（）
A. is performed by the dam methylase
B. is delayed for ~10 min after DNA synthesis
C. is related to the initiation of DNA replication
D. all of the above
Sometimes deaminated bases must be removed from DNA because（）
A. they denaturate the molecule
B. they form thymine dimers
C. they pair incorrectly during replication
D. the mRNA formed may be irregular
Deletion of 4 bases from the coding region of a gene will give（）
A. nonsense mutations
B. missense mutations
C. silent mutations
D. frameshift mutations
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