Biotechnology Principles and Processes Test - 5

To track the position of DNA during gel electrophoresis tracing dye should be used. Gel electrophoresis technique segregates the DNA pieces according to size.

DNA was first used to aid a criminal investigation by Professor Jeffreys in 1986. This investigation used DNA fingerprinting techniques to link semen stain samples, collected from two rapes/murders that had occurred three years apart in 1983 and 1986, in a small village in Leicestershire, UK.

Restriction enzymes are used to cut the DNA at specific scissors. The cut piece of DNA is linked with vector DNA to transfer the gene to specific target.

A. tumifaciens has exceptional ability to transfer a particular DNA segment to the tumer inducing plasmid into the nucleus of infected cells.

Agrobacterium tumifaciens is called as the natural genetic engineer as in this bacterium brings about gene transfer to plants without involvement of human.

All the enzymes at higher temperature become inactive. Denaturation is done at high temperature as it leads to breaking down of hydrogen bonds between the bases of polynucleotides.

The techniques of genetic engineering which include creation of recombinant DNA, use of gene cloning and gene transfer,helps to overcome the limitation of undesired genes getting multiplied along with the desired genes in traditional hybridisation techniques and allow us to isolate and introduce only one or a set of desirable genes without introducing undesirable genes into the target organism. It is a part of biotechnology.

Genetic engineering involves identifying DNA with desirable genes, introduction of identified DNA into the host, maintenance of introduced DNA in host and transfer of DNA in it progeny.

If a DNA is fragmented using Eco RI, the fragments that will be produced are 5’ G AATTC3’. The palindrome in DNA sequence of base pairs that reads same on 3’CTTAA G5’ two strands when orientation of reading is kept same.

Genetic engineering is accomplished in three basic steps. These are

• The isolation of DNA fragments from a donor organism;
• The insertion of an isolated donor DNA fragment into a vector genome and
• The growth of a recombinant vector in an appropriate host.

The origin of replication (also called the replication origin) is a particular sequence in a genome at which replication is initiated.

This can either involve the replication of DNA in living organisms such as prokaryotes and eukaryotes, or that of DNA or RNA in viruses, such as double-stranded RNA viruses.

Origin of replication is essential for replication of particular DNA segment.