Category: Biology Second Paper

A hole is created in the host cell membrane by the electric field. Recombinant DNA is introduced into the host cell through this pore.

1. Target DNA selection and separation (Target DNA selection): First the target DNA is selected. While selecting the desired DNA, one should keep in mind that it should be healthy, strong, disease free and of superior breed. Selected cells are first lysed slightly. Cell membranes are broken down using enzymes like lysozyme (bacterial cells), chitinase (fungal cells), cellulase (plant cells). The lysed cells are then centrifuged into test tubes. A quantity of cesium chloride solution is introduced into a centrifuge test tube. The solution is then centrifuged. As a result, a band of DNA is formed on the test tube. DNA is mixed with other components to form a homogenate. DNA is separated from the homogenate using enzymes such as protease (protein), ribonuclease (RNA), amylase (sugar), lipase (fat). The purified DNA is then precipitated as a thread by immersion in a cold ethanol solution. The desired DNA is selected from the degraded DNA.
2. Host selection: The host is selected to carry the required part of the desired DNA. In this case, the bacterium Agrobacterium tumefaciens works as a good carrier. The required part of the desired DNA is attached to the plasmid DNA located in the cytoplasm of this bacterium. In some cases carriers such as cosmids, phagemids, artificial chromosomes etc. are used.
3. Excision of the desired DNA at a specific location: Several sections are cut from the desired DNA by applying restriction enzymes. Corresponding segments are also excised from the carrier plasmid DNA using the same enzyme. This process is called restriction digestion. Restriction enzymes cleave double-stranded DNA to form single-stranded ends. It is called sticky end.
4. Placement of the desired DNA molecule into the carrier plasmid DNA molecule: The desired fragment is separated from the DNA fragments by gel electrophoresis. The desired DNA fragment is then picked up on a nylon screen by Southern blotting. The required gene is then identified using a radioactive probe. The identified DNA is ligated to plasmid DNA with ligase enzymes. Recombinant DNA is produced by ligation of the desired DNA with the carrier plasmid DNA.
5. Introduction of Recombinant DNA into the Host: The host is selected to carry the recombinant DNA. In this case E. coli bacteria act as host. Recombinant DNA is introduced into host cells. But under normal conditions bacteria do not accept other plasmids. If the culture medium in which the bacterium is grown is heated and a suitable environment is created by adding calcium, the bacterium takes up another plasmid. The process of introducing recombinant DNA into bacterial cells is called transformation. Besides, recombinant DNA is introduced into host cells through conjugation, microinjection, liposome, electroporation etc.
6. Evaluation of expression of recombinant DNA: It is checked whether the work of making recombinant DNA has been done correctly. This test is done by genetic probe method. Selectable marker of plasmid DNA is used in this process. Antibiotic resistance genes are inserted into the recombinant DNA. The host bacteria are then grown in culture medium. Bacteria into which the antibiotic resistance gene was inserted grew in the culture medium and formed colonies. From this, it can be understood that the work of making recombinant UghA has been done correctly.
7. Introduction of Recombinant DNA into Plant Body: The prepared recombinant DNA is introduced into the desired plant body in tissue culture process. Later new plants are obtained from those cells. Such plants are called transgenic plants.

Check if the recombinant DNA has been made correctly. This test is done by genetic probe method. Selectable marker of plasmid DNA is used in this process. Antibiotic resistance genes are inserted into the recombinant DNA. The host bacteria are then grown in culture medium. Bacteria into which the antibiotic resistance gene was inserted grew in the culture medium and formed colonies. From this, it can be understood that the work of making recombinant UghA has been done correctly.

Hosts are selected to carry the recombinant DNA. In this case E. coli bacteria act as host. Recombinant DNA is introduced into host cells. But under normal conditions bacteria do not accept other plasmids. If the culture medium in which the bacterium is grown is heated and a suitable environment is created by adding calcium, the bacterium takes up another plasmid. The process of introducing recombinant DNA into bacterial cells is called transformation. Besides, recombinant DNA is introduced into host cells through conjugation, microinjection, liposomes, electroporation etc.

Carriers are selected to carry the required portion of the desired DNA. In this case, the bacterium Agrobacterium tumefaciens works as a good carrier. The required part of the desired DNA is attached to the plasmid DNA located in the cytoplasm of this bacterium. In some cases carriers such as cosmids, phagemids, artificial chromosomes etc. are used.

First the target DNA is selected. While selecting the desired DNA, one should keep in mind that it should be healthy, strong, disease free and of superior breed. Selected cells are first lysed slightly. Cell membranes are broken down using enzymes like lysozyme (bacterial cells), chitinase (fungal cells), cellulase (plant cells). The lysed cells are then centrifuged into test tubes. A quantity of cesium chloride solution is introduced into a centrifuge test tube. The solution is then centrifuged. As a result, a band of DNA is formed on the test tube. DNA is mixed with other components to form a homogenate. DNA is separated from the homogenate using enzymes such as protease (protein), ribonuclease (RNA), amylase (sugar), lipase (fat). The purified DNA is then precipitated as a thread by immersion in a cold ethanol solution. The desired DNA is selected from the degraded DNA.

1. Enzyme: Enzymes used in recombinant DNA technology are restriction, lysozyme, polymerase, ligase, alkaline phosphatase etc.
2. Vector: The vectors used in recombinant DNA technology are – plasmid, phagemid, virus, cosmid, transposon, artificial chromosome etc.
3. Host: The host used in recombinant DNA technology is E. coli, yeast, bacteria, plant cells, animal cells etc.

1. Gene fusion: The process by which two or more genes are joined to create a hybrid gene is called gene fusion. Cancer research is done by attaching another gene to a cancer-causing gene.
2. Protoplast Fusion: Fusion of two genes by joining the protoplasts of two cells is called protoplast fusion. The new plant resulting from the fusion of potato and tomato plant protoplasts is named pomato.
3. Gene amplification (Gene amplification): The process in which multiple copies of a gene are made is called gene amplification. In this process, bacteria are used to produce a large amount of vitamins, antibiotics, amino acids, etc.
4. Creation of hybridoma (Creation of hybridoma): The process in which cancer cells are combined with specific antibody-producing B-lymphocyte cells to create hybrid cells is called hybridoma. In 1975, Cesar Milstein and Georges Kohler discovered the hybridoma method.
5. Recombinant DNA Technology: By following and applying scientific and engineering principles, new DNA with new characteristics is created by combining desired DNA with plasmid DNA is called recombinant DNA.

Hybridoma is the process in which a cancer cell fuses with a specific antibody-producing B-lymphocyte cell to form a hybrid. In 1975, Cesar Milstein and Georges Kohler discovered the hybridoma method.

The process by which multiple copies of a gene are made is called gene amplification. In this process, bacteria are used to produce a large amount of vitamins, antibiotics, amino acids, etc.