One way to fight viral infections is to prevent viruses from replicating their DNA. Without DNA replication, the virus cannot multiply. Some viral drug therapies cause the introduction of fake nucleotides into cells. When the virus uses one of these fake nucleotides in an attempt to replicate
its DNA, the fake nucleotide doesn't work and DNA replication is halted. For example, AZT, a drug used to fight the human immunodeficiency virus (HIV) that causes AIDS, introduces the fake thymine-containing nucleotide (shown at left) into cells.
Examine the structures of the real nucleotide and the AZT fake nucleotide. Propose a mechanism for how this fake nucleotide halts DNA replication.
Here we have to Propose a mechanism for how the fake nucleotide halts DNA replication.