Wednesday, December 4, 2019
Genetics Engineering Essay Example For Students
 Genetics Engineering Essay  Genetic engineering is an umbrella term that can cover a wide range of ways of  changing the genetic material  the DNA code  in a living organism. This code  contains all the information, stored in a long chain chemical molecule, which  determines the nature of the organism. Apart from identical twins, genetic  make-up is unique to each individual. Individual genes are particular sections  of this chain, spaced out along it, which determine the characteristics and  functions of our body. Defects of individual genes can cause a malfunction in  the metabolism of the body, and are the roots of many genetic diseases.   In  a sense, man has been using genetic engineering for thousands of years. We  werent changing DNA molecules directly, but we were guiding the selection of  genes. For example the domestication of plants and animals. Recombinant DNA  technology is the newest form of genetic engineering, which involves the  manipulation of DNA on the molecular level. This is a totally new process based  on the science of molecular biology, a relatively new science only forty years  old. It represents a major increase in our ability to improve life.   But a  negative aspect is that it changes the forms of life we know of, possibly  damaging our environment It has been known for some time that genetic  information can be transferred between micro-organisms. This is process it done  via plasmids (small circular rings of DNA) or phages (bacterial viruses). Both  of these are termed vectors, this is because of their ability to move genetic  material. In general this is limited to simpler species of bacteria.  nevertheless, this can restriction can be overcome with the use of genetic  engineering because it allows the introduction of any gene. While genetic  engineering is beginning to be used to produce enzymes, the technology itself  also depends on the harnessing of enzymes, which are available in nature.         In the  early 1970s Herbert Boyer, working at the University of California Health  Science Centre in San Francisco, and Stanley Cohen at Stanford University found  that it was possible to insert into bacteria genes they had removed from other  bacteria. First they learned the trick of breaking down the DNA of a donor  organism into manageable fragments. Second, they discovered how to place such  genes into a vector, which they used to ferry the fragments of DNA into  recipient bacteria. Once inside its new host, a transported gene divided as the  cell divided, leading to a clone of cells, each containing exact copies of the  gene. This technique became known as gene cloning, and was followed by the  selection of recipient cells containing the desired gene. The enzymes used for  cleaving out the DNA pieces act in a highly specific way.   Genes can, therefore,  be removed and transferred from one organism to another with extraordinary  precision. Such manoeuvres contrast sharply with the much less predictable gene  transfers that occur in nature. By mobilising pieces of DNA in this way  (including copies of human genes), genetic engineers are now fabricating  genetically modified microbes for a wide range of applications in industry,  medicine and agriculture. The underlying idea of transferring genes between  cells is quickly explained. However the actual practice is an extremely  complicated process. The scale of the problem can be gauged from the  astronomical numbers involved: the DNA of even the simplest bacterium contains  4,800,00 pairs of bases.   But there is only one copy of each gene in each cell.  First, restriction enzymes are used to snip the DNA into smaller pieces, each  containing one or just a few genes. These enzymes cut DNA in very precise ways.    Commentary On Brave New World Essay The cuts produce pieces of double  helix with short stretches of single stranded DNA at each end. These are know as  sticky ends. If the enzyme is allowed to act for a limited time, it may not have  a chance to attack all the recognition sequences in the chain. This will result  in longer fragments. As in natural DNA replication, bases have an inherent  propensity to join up with their partners A with T, for example, and G with C.  So too with sticky ends.   For example, the sequence TTAA will tend to  re-associate with AATT. Genetic engineers use another type .    
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