What is the direction of DNA synthesis and why does it matter?
DNA is always synthesized in the 5′-to-3′ direction, meaning that nucleotides are added only to the 3′ end of the growing strand. As shown in Figure 2, the 5′-phosphate group of the new nucleotide binds to the 3′-OH group of the last nucleotide of the growing strand.
What causes mutation in DNA?
A mutation is a change in a DNA sequence. Mutations can result from DNA copying mistakes made during cell division, exposure to ionizing radiation, exposure to chemicals called mutagens, or infection by viruses.
What is an error in DNA replication called?
mistakes are called. mutations. mutations are. changes in the sequence of DNA. mistakes can be made during the DNA replication process but DNA replication process has features that reduce mutations.
What is exonuclease in DNA replication?
Exonucleases can act as proofreaders during DNA polymerisation in DNA replication, to remove unusual DNA structures that arise from problems with DNA replication fork progression, and they can be directly involved in repairing damaged DNA.