Question

1. How are each of the following used in biotechnology?
a. restriction enzymes
b. cloning vectors
c. PCR

Answer 1

Restriction enzyme uses in Biotechnology

Restriction enzymes are used to cut DNA into small fragments and the cuts are made at a particular nucleotide sequence. This function of restriction enzymes is used as a tool in several molecular genetics techniques.

Restriction enzymes are also used in mapping of DNA fragments or genomes. Mapping involves determining the restriction enzyme site order in the genome. These maps are beneficial for other genetic analysis. The restriction enzymes are often used to verify the specificity of the DNA fragment depending on the known restriction enzyme sites that it consists of.

Another use of restriction enzymes is to create recombinant DNA molecules comprising of DNA fragments from two different organisms. Restriction enzymes are used to digest the DNA from the organism and in preparing the DNA for cloning. The bacterial plasmid or bacterial virus is digested using an enzyme that gives rise to compatible ends. The ends might have complementary overhanging sequences. DNA from the experimental organism is mixed with DNA from virus and plasmid and these DNAs are joined with an enzyme called DNA ligase. These enzymes are used in the technique called restriction fragment length polymorphism.

Cloning Vector uses in Biotechnology

Vectors are the tools utilized by the molecular biologists to include genes or fragments of foreign DNA into the host cells. The vectors that insert the foreign DNA into the bacterial cells are plasmids and bacteriophages. Other vectors are Cosmids, yeast cloning vectors, Ti&Ri plasmids target host cell bacteria, artificial chromosome vectors.

Phage vectors are used to clone large DNA fragments. Bacteriophage vectors infect bacteria and transform the DNA of bacteria.

Phage M13 vectors are used for getting single stranded copies of the DNA.

Cosmids are used to mix the lambda chromosome parts with that of plasmids.

PCR application in biotechnology

Polymerase chain reaction is considered as a sensitive tool in the diagnosis of various diseases in humans. Disease can be identified using RFLP analysis. So, PCR is used in clinical diagnosis.

PCR is also used in forensic science in the identification of the criminal. It is also used in the diagnosis of embryo sex determination, bacterial infections, retroviral infection, and in cancer.

PCR helps in studying the gene in gene therapy. PCR is useful in the genomic studies to compare the genomes of two organisms and in the identification of differences between them.

PCR plays an important role in the phylogenetic analysis with the help of very small quantities of DNA extracted from fossils, bones, hair, mummified tissues. This DNA is amplified using PCR.