DNA Replication

elemis

Before I ask my question, I would like to state that I am not a Biology student. I am actually a Chemistry student who has a small section on Biochemistry in his syllabus.

Now, my problem lies with part (ii).

Mechloroethamine obviously hold the DNA strands together and prevents the DNA helix from uncurling/unzipping. Hence, the very first stage in replication is impeded.

How cis-platin affects DNA replication is eluding me. I know that Guanine normally forms 3 hydrogen bonds with Cytosine. However, it seems to be forming only one hydrogen bond in this case.

Could someone prod me in the correct direction ?

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Abod

Read this, it might be helpful.

aroc91

This should help as well-

http://pharmacologycorner.com/cispla...deo-animation/