Describe how plasmids and viruses can act as vectors, which take up pieces of DNA, then insert this recombinant DNA into other cells
Plasmids (circular structure) are found in bacteria cell, which are a right of bacteria DNA (as bacterias are prokaryotes and do not have proper nucleus). They are particularly small and don't carry many "information".
Essentially, a virus has a protein shell called a capsid (pentagonal structure). Inside there will be a nucleic acid, possibly DNA or RNA. The virus has no other cellular components, such as cytoplasm or nucleus.
A human chromosome (long threadlike structure) is made out of DNA.
Genes are section of chromosome.For instance, a gene is responsible for insulin, or hormone controlling blood sugar level.
1. The restriction enzyme is selected that can cut the DNA of the section which made up the gene for insulin.
2. Having cut the genes, we will take the plasmid of bacteria and cut it with exactly the same restriction enzyme. (Human enzyme that cuts out the human gene also cuts out the plasmid.) This will leave a broken ring structure.
3. Introduce into the cut plasmid the human insulin gene. Both plasmid and human genes are composed of DNA. The human gene is then inserted into the plasmid.
4. Complete the process by applying DNA Ligase enzyme to join the DNAs together. This combination of human genes + plasmid is known as recombinant DNA.
Hosting Recombinant DNA
(way in which recombinant DNA is transferred into other cells)
It is necessary to transfer the recombinant DNA into the host cell. In this instance we will use the virus. Inside the virus is the nucleic acid such as DNA or RNA. Around it is the protein.
1. Remove nucleic acid from the virus. We only want the capsid protein shell.
2. The plasmid are taken up by the virus. The virus is going to act as a vector of the recombinant DNA, which will transfer it into the host cell.
The reason why we have chosen virus is that the virus is known as a phage, and it infect bacterial cells. The virus is able to attach to the cell member of the bacteria and insert the recombinant DNA into the host cell.
At the end of this process we have a bacterial cell which now contains the recombinant DNA including the human gene for insulin.
Notice that the bacteria still has its own normal DNA plus DNA from another organism. This organism is known as transgenic.
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