Question

What are the major similarities and differences between DNA repair in prokaryotes versus eukaryotes?

Answer 1

• Similarities in DNA replication between Prokaryotes and eukaryotes:-

For all prokaryotic and eukaryotic organisms the steps for replication of DNA are usually the same. The enzyme called Genome helicase accomplishes unwinding of the DNA. New DNA strands are generated orchestrated with enzymes called polymerases.

There is also a phenomenon called semi-conservative replication of both types of species. In this phenomenon, the individual DNA strands are formed in different directions, creating both a leading and a lagging strand.Lagging strands are formed by creating small fragments of DNA, called Okazaki fragments, which are gradually combined. All kinds of organisms often start new DNA strands with a tiny RNA primer.

• Difference in DNA replication between Prokaryotes and eukaryotes:-

The variations between prokaryotic and eukaryotic replication of DNA are largely related to the similarities in the size and complexity of these species ' DNA and cells. The eukaryotic average cell has 25 times more DNA than a prokaryotic cell.

There is only one point of origin in prokaryotic cells, replication takes place in two opposite directions at the same time, and occurs in the cytoplasm of the cell.On the other hand, eukaryotic cells have many points of origin, and use unidirectional replication within the nucleus of the cells. Prokaryotic cells take one or two forms of polymerase, while eukaryotes have four or more forms.

Replication happens in prokaryotic cells also at a much faster rate than in eukaryotes. Some bacteria only take 40 minutes, while animal cells like humans could take up to 400 hours. Additionally, eukaryotes also have a distinct mechanism at the ends of their chromosomes for replicating the telomeres.Prokaryotes have no ends to synthesise for their circular chromosomes. Eventually, brief replication in prokaryotes occurs almost constantly, but eukaryotic cells only undergo replication of DNA during the cell cycle's S-phase.