Consider the structure of thymine, shown on the left in Figure 2.3 above, and compare to the structure of pyrimidine X on the right. What would be the impact if X is incorporated into the structure of a DNA strand in place of thymine?

What will be an ideal response?


Where thymine has a nonpolar group, pyrimidine X has a polar functional group. If incorporated into a DNA strand pyrimidine X would not form the proper hydrogen bonds with either A or G, resulting in mismatches between DNA strands or, more seriously, disruption of the DNA strand. This type of alteration can lead to mutations in the DNA.

Biology & Microbiology

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The difference between a single nucleotide polymorphism (SNP) and a point mutation is that:

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