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Question
Which of the following statements explains why the thymine analog, 5-bromouracil (5-BU), can cause mutations in DNA when it is inserted in place of a site normally occupied by T?a. the bromine of 5-BU is similar in size to the methyl group of T and thus pairs with A
b. 5-BU is often found as the enol tautomer that hydrogens more effectively with G than with A
c. the bromine is subject to nucleophilic attack by a methyl transferase resulting in newly synthesized DNA being recognized as the methylated parent strand
d. the 5-BU is subject to removal resulting in a frame-shift mutation
e. none of the above
Answer
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