DNA replication is a crucial process where the cell copies their genome and replicates it into two individual strands, this process is typically crucial during cell replication. DNA, which stands for deoxyribonucleic acid, contains the biological information for the cell to function, develop and reproduce. Though when a cell undergoes cell division that requires for the quantity of DNA to increase for there to be DNA present in both parent and daughter cells, which is where DNA replication takes place. DNA replication occurs within the nucleus for eukaryotic cells, for prokaryotic cells DNA replication occurs within the cytoplasm.
DNA replication relies heavily upon enzymes to aid with the process, including DNA polymerase I,II and III, DNA helicase, RNA primase, SSB proteins and many more.
The first stage within DNA replication is unwinding and separating the DNA strands from each other. Topoisomerase unwinds the DNA from it’s double helix structure allowing for DNA helicase, using ATP energy, to separate the two strands.The DNA helicase enzyme typically travels in between the two strands,referred to as the ‘replication fork’. Then Single Strand Binding Proteins attach to the exterior of the replication fork on both strands to prevent the two strands from reconnecting together.
The second stage is where the construction upon the template strands begins. RNA primer synthesizes an enzyme called RNA primase. RNA primase acting as the foundation for the remaining strand on both template strands. RNA primase can only build from the 5’ to 3’ direction therefore beginning on the template strand from the 3’ end as both strands need to be opposite from each other. Then DNA polymerase reads the template strand’s nitrogenous bases to match the pairs, for example Guanine to Cytosine and Adenine to Thymine. DNA polymerase can only read the template strand 3’ to 5’ and build 5’ to 3 following the unzipping of the replication fork. Though one strand, known as the lagging strand, since it can only build 5’3 this strand’s primase would have been places near the replication fork, though as the DNA Helicase continues to unzip that means that the RNA primer must keep returning up to the fork to place more RNA primers for the DNA polymerase to build Though the DNA polymerase does not completely build until the last RNA primase leaving each Primase and Polymerase to be left in fragments, also referred to as ‘Okazaki fragments’.
The last stage of DNA replication is for checking and replacements. DNA ligase seals the gaps between each Okazaki Fragments to make them one continuous strand. Then DNA polymerase II comes in and proof-reads the nitrogenous bases to check if they are correctly matched, if they are not they will replace it with the correct ones.
After all these steps are complete the two DNA strands will separate when the DNA helicase comes to the end and will return back to it’s double helix structure with two DNA.
DNA replication is a crucial process where the cell copies their genome and replicates it into two individual strands, this process is typically crucial during cell replication. DNA, which stands for deoxyribonucleic acid, contains the biological information for the cell to function, develop and reproduce. Though when a cell undergoes cell division that requires for the quantity of DNA to increase for there to be DNA present in both parent and daughter cells, which is where DNA replication takes place. DNA replication occurs within the nucleus for eukaryotic cells, for prokaryotic cells DNA replication occurs within the cytoplasm.
DNA replication relies heavily upon enzymes to aid with the process, including DNA polymerase I,II and III, DNA helicase, RNA primase, SSB proteins and many more.
The first stage within DNA replication is unwinding and separating the DNA strands from each other. Topoisomerase unwinds the DNA from it’s double helix structure allowing for DNA helicase, using ATP energy, to separate the two strands.The DNA helicase enzyme typically travels in between the two strands,referred to as the ‘replication fork’. Then Single Strand Binding Proteins attach to the exterior of the replication fork on both strands to prevent the two strands from reconnecting together.
The second stage is where the construction upon the template strands begins. RNA primer synthesizes an enzyme called RNA primase. RNA primase acting as the foundation for the remaining strand on both template strands. RNA primase can only build from the 5’ to 3’ direction therefore beginning on the template strand from the 3’ end as both strands need to be opposite from each other. Then DNA polymerase reads the template strand’s nitrogenous bases to match the pairs, for example Guanine to Cytosine and Adenine to Thymine. DNA polymerase can only read the template strand 3’ to 5’ and build 5’ to 3 following the unzipping of the replication fork. Though one strand, known as the lagging strand, since it can only build 5’3 this strand’s primase would have been places near the replication fork, though as the DNA Helicase continues to unzip that means that the RNA primer must keep returning up to the fork to place more RNA primers for the DNA polymerase to build Though the DNA polymerase does not completely build until the last RNA primase leaving each Primase and Polymerase to be left in fragments, also referred to as ‘Okazaki fragments’.
The last stage of DNA replication is for checking and replacements. DNA ligase seals the gaps between each Okazaki Fragments to make them one continuous strand. Then DNA polymerase II comes in and proof-reads the nitrogenous bases to check if they are correctly matched, if they are not they will replace it with the correct ones.
After all these steps are complete the two DNA strands will separate when the DNA helicase comes to the end and will return back to it’s double helix structure with two DNA.