Exposure to nitrous acid (see Section 19-16), sometimes found in cells, can convert cytosine to uracil.(a) Propose a mechanism for this conversion.(b) Explain how this conversion would be mutagenic upon replication.(c) DNA generally includes thymine, rather than uracil (found in RNA). Based on this fact, explain why the nitrous-acidinduced mutation of cytosine to uracil is more easily repaired in DNA than it is in RNA.*

Exposure to nitrous acid (see Section 19-16), sometimes found in cells, can convert cytosine to uracil.(a) Propose a mechanism for this conversion.(b) Explain how this conversion would be mutagenic upon replication.(c) DNA generally includes thymine, rather than uracil (found in RNA). Based on this fact, explain why the nitrous-acidinduced mutation of cytosine to uracil is more easily repaired in DNA than it is in RNA.*

Organic Chemistry

9th Edition

ISBN:9781305080485

Author:John E. McMurry

Publisher:John E. McMurry

Chapter25: Biomolecules: Carbohydrates

Section25.SE: Something Extra

Problem 35MP

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