Answer:
This question is incomplete as it lacks options; the options are:
A) Bond X only
B) Bond W only
C) Bonds Y and Z at the same time
D) Bonds W and Z at the same time
The answer is C. Bond Y and Z at the same time
Explanation:
A DNA molecule is a double-stranded molecule made up of nucleotide units. According to this question, radiation can damage the nucleotides in the DNA molecule. However, the cell can repair this DNA molecule by removing the single damaged nucleotide and replacing it with an undamaged one.
In this case, the cytosine nucleotide is the damaged nucleotide. To repair this DNA in the image, the covalent bond holding the one nucleotide to another in one of the DNA strands must be broken.
The sugar-phosphate bonds as represented by letters Y and Z are the bonds that could be broken to replace the cytosine nucleotide by an undamaged one, without affecting the biological information coded to the DNA molecule. The bonds holding the neighboring nucleotides are also broken during the repair process. Note that, this form of repair is called BASE EXCISION REPAIR