Polymerase chain reaction practical, Genetics Essay

Polymerase chain reaction practical, Genetics - Essay Example Currently, there are hundreds of different types of PCR are being used in different laboratories but the basic principle remains same. The overall process of PCR can be summarized as follows. 1) Mixture of all constituents of PCR like dNTPs, Primers (forward and reverse), Buffer and template DNA will be mixed in desired concentration. 2) The first step is amplification, where the temperature is set at 94C for 2-5 minutes for denaturation of double stranded DNA, a process called initial denaturation, 3) After initial denaturation, sample is kept for 30 sec at 94C for further denaturation, 4) After denaturation temperature is brought down to 55-60C for 30sec to allow annealing of primer with specific DNA site called annealing temperature. 5) The temperature is now brought up to the 72C for polymerase to start new DNA synthesis using primer as starting material. 6) After extension, the cycles are repeated for almost 30 times to get 230 copy of initial DNA template. Finally, after 3 cycl e extension is be performed at 72C for 5 min to complete any unamplified reaction. Figure 1 shows steps involves in PCR. Development of PCR and identification of DNA as signature molecules for individual leads to introduction of DNA based technique for establishment of parental relation and subsequently for crime and criminal detection. Based on DNA sequence of humans it was found that there are many places in entire DNA that are conserved nucleotide repeats and based on size or length of these sequences they are termed as micro and mini satellite (4). It was found that number of repeat in these sequences varies from person to person and inherited from parents to child makes it ideal choice for criminal identification. Later, this process was termed as DNA fingerprinting. Moreover, development of PCR made this technique more powerful and realistic compared to any other technique for criminal identification, since most of the time, the specimen obtained in the crime site is always in less quantity. This small part of body or body fluids like blood, sperm, saliva or even hair is sufficient to isolate DN A and then amplification with PCR make it possible to do different analysis on it. Here the aim of this experiment was to understand fundamental principle and use of polymerase chain reaction and based on that to understand how PCR is used in DNA fingerprinting based crime investigation and criminal identification 2. Methods: 2.1 Buccal DNA extraction: Ten ml, 0.9% saline solution was rubbed vigorously against the cheeks for 10 seconds. The sample (extract from the bucaal cavity) was then transferred into 15 ml centrifuge tube and centrifuged at 2000 g for 10 minutes for the pellet. Thereafter, 500 l of chelex beads were added into the pellet and resuspended with the chelex by pipetting in and out various times such that there are no visible clumps of cells. Five hundred microliter of the aliquot was transferred into 1.5ml microfuge tube and was boiled into a hot block at 100C for 10 mins. The sample was then spin for 30 secs top speed to spin down chelex. Fifty microliter of the fresh supernatant was transferred

The effect of terrorism on the global economy Essay

The effect of terrorism on the global economy - Essay Example and all of the countries it trades with. The federal government, in what some might term a ‘knee-jerk’ reaction to the attack, spent unprecedented amounts of money on questionable programs and ventures in an effort to ‘provide security’ to its citizens. â€Å"The President has requested a significant increase in security-related programs in the context of the budget for 2003. Additional spending of $48 billion was proposed for national defense (an increase of 14 percent from the previous year). In addition, the President asked Congress for an appropriation of $38 billion for homeland security, compared to $20 billion spent in 2001† (Looney, 2002). The combination of a stunned economy, a flat-line growth in the job market and dwindling government resources made its affects known worldwide. This paper will examine how the events of 9/11 influenced many aspects of the U.S. economy and examples of its global consequences. The U.S. was enjoying a period of vigorous economic expansion during the second Clinton administration, a period that saw the nation’s first budget surpluses in 40 years. This growth was fueled largely because of a general confidence in the nation’s economic health and an increase in worker’s productivity. This time of prosperity was over by the latter part of the year 2000 as the trend in business appeared to reflect a lessening confidence in the direction of the national economy. Corporations, especially those in the technical industries, began systematically downsizing, outsourcing and employing other means of economizing because of steady revenue losses. The economy had shown signs of weakening the entire year of 1999, and by the end of 2000, the manufacturing segment was also steadily shrinking as was evidenced by the lack of equipment orders, profits and number of employees. This trend was experienced many other industries