Thursday, January 30, 2020
The First Essay Example for Free
The First Essay In the first part of this lab, E. coli cells were transformed with an R-plasmid carrying a tetracycline resistant gene, giving rise to tetracycline resistant E. coli strain. This was accomplished through transformation, which allowed E. coli to directly uptake the naked DNA molecule carrying the antibiotic resistant gene (1). However, in order to take up the DNA and incorporate them into their genome via recombination, cells must be competent (1). Therefore, E. coli cells which are not competent under normal conditions were treated with cold and high concentration of CaCl2, in order to make them artificially competent (1). The transformants were grown on the LB with the tetracycline antibiotic, and on the LB without the tetracycline. Then the viable competent cells and the viable cells were counted to calculate the frequency of transformation. In the second part of the lab, lateral gene transfer by generalized transduction was done on E. coli cells. In the process of transduction, the transfer of genes is facilitated by bacteriophage, which is a virus that infects a bacterial host (1). Generalized transduction involves lytic infections that kill the bacterial cells, and during the process, bacterial DNA is packaged into a new phage head which in turn injects the DNA into another bacterium (1). In this lab, P1vir phage was used and grown on the donor strain by making a phage lysate. P1vir phage kills bacterial cells by lytic infections, which is required in the generalized transduction (1). On the other hand, the wild-type p1 is a lysogenic phage and therefore could not be used for the generalized transduction (1). In order to prevent excessive killing of the recipient E. oli strain, the P1vir lysate was tittered by serial dilutions. This would also prevent infection and lysis of the transducing particle. In generalized transduction, trp-pyrF region of CSH61 chromosome, which was the P1vir lysate, was laterally transferred to the recipient CSH54 strain. The genotypes of transductants were tested by patching them onto a Petrie plate lacking tryptophan and uracil, whi ch will allow growth of trp+, pyrF+, and not the trp+,pyrF- transductants. Trp gene encodes for trypsin, while the pyrF gene encodes for pyramidines, such as uracil. Thi, his, and pro genes encode for thiamine, histidine, and proline respeictively (1). Finally, the frequency of transductant was used to obtain the distance between the trp and pyrF gene. Discussion In the transformation experiment, E. coli cells were transformed with Plasmid DNA containing the tetracycline resistant gene, and were tested for competency by growing them in LB in presence of tetracycline antibiotic. Tetracycline is a broad spectrum antibiotic that works by inhibiting translation, thus inhibiting protein synthesis. It attaches to the 30S subunit of ribosome and prevents the charged aminoacyl-tRNA from binding (3). As shown on Table 1, Tube 3 and Tube 2 did not have any growth of E. coli cells. Tube 2 contained E. coli cells only, and when cultured on the LB plate in presence of tetracycline antibiotic, the growth was inhibited by the antibiotic. Because the E. coli cells in tube 2 lacked the tetracycline resistant gene contained in the plasmid DNA, it was unable to grow in the presence of tetracycline antibiotic. Tube 3, lacked the E. coli cells and so, there were no cells to grow in the LB plate with or without the tetracycline. Tube 3 instead was used as a control, to test for contamination in the plasmid DNA and the calcium chloride. In tube 1, which contained the E. coli cells and the plasmid DNA containing the tetracycline resistant gene, transformation occurred. As a result, E. coli cells have acquired the tetracycline resistant gene, being able to grow on the LB plate in the presence of the tetracycline antibiotic. Therefore the viable competent cells were counted from tube 1 contents in 102 diluted LB (with antibiotic), which had cells between 30 and 300 colonies. On the other hand, the total viable cells were counted from tube 1 in 106 diluted plate that was grown on LB without the antibiotic. As shown on table. 2, the viable competent cells were calculated to be 24350 cells/100ul and the total viable cells were found to be 370,500,000 cells/100ul. Finally, the transformation frequency, which is the ratio of transformants per viable cell, was calculated and was found to be 6. 49 x 10-05 as shown on table 2. In the generalized transduction experiment, trp gene from the donor strain of CSH61 (P1vir lysate) was laterally transferred to the recipient strain, CSH54. CSH61 strain are trp+, pyrF+ and the CSH54 strain are trp-, pyrF-, and because trp and pyrF are linked together on the same chromosomal fragment, they are cotransduced (1). The transductants were identified by selecting for the trp+ marker by growing in absence of tryptophan, however the pyrF marker may be present or absent, depending on the crossover event during recombination. This was identified by patching the transductants onto a Petrie plate lacking tryptophan and uracil. The trp+, pyrF+ transductants will be able to synthesize both tryptophan and uracil, and therefore will grow in this minimal medium (1). However, trp+, pyrF- transductants cannot grow in the medium, because they wonââ¬â¢t be able to synthesize uracil (1). As shown on table 3, 57. 5% of transductants were trp+, pyrF+ while 42. 5% were trp+, pyrF-. This means trp is cotransduced with pyrF at 57. 5% frequency, which indicates that they are very closely linked. Markers which are separated by less than 0. 5 minutes are cotransduced at 35-95%, and so, trp which cotransduced with pyrF at 57. 5%, is very closely linked (1). This closely matches the actual cotransduction frequency of 55% between trp and pyrF in E. oli (2). According to the Wu formula, the cotransduction frequency of 57. 5% yielded distance of 0. 084 minutes, which was very close to the distance of 0. 09 minutes at cotransduction frequency of 55% found in literature (2). Bacterial genes can also be analyzed by a method known as Southern blotting (4). In this method, DNA is treated with restriction enzymes, which cuts the DNA into fragments of different size. Then the fragments are run on an agarose gel by electrophoresis, which separates the fragments by size.
Tuesday, January 21, 2020
America Censored: A Battle of Rights Essays -- Censorship Censoring Me
America Censored: A Battle of Rights Welcome to the United States of America. This is the Land of the Free and the Home of the Brave. A place where our forefathers once gathered and drew up the foundation for which we live our lives. The Constitution of the United States grants us a certain amount of freedoms for which we cannot be punished for. The first amendment to this constitution of the Constitution allows us the freedom of speech, religion, the right to assemble, and to express ourselves in a way in which we feel fit. Under this amendment, people such as musicians and newsmen and able to write and speak what they feel without being told that it is wrong. They cannot be manipulated to change their thoughts or views on a topic, or can they? Even though the first amendment protects freedom of speech and press people everyday fight not to be censored because they write and speak what they feel. When people are censored for speaking their mind, it shows that the first amendment is nothing more than a falsehood that pr otects some but not all. Letàs start this off at the very beginning. What is Censorship? According to The American Heritage College Dictionary to censor is, "To examine in order to suppress or delete anything considered objectionable" (American Heritage College Dictionary 226). So basically it is when a select group of people go through books, movies, and music, and ask that anything that might be seen as offensive to a group of people or anyone in general be removed from the publication. Right away you can see how by doing this a personàs first amendment is being violated. If, as Americans, we are granted the freedom of speech and expression then having something you write or say censored directly violates th... ... day they die. Why donà t we let them use it and everyone just worry about themselves. If you donà t like something then stay away from it. Itàs as simple as that. If it wasnà t for the first amendment people like Tipper Gore wouldnà t even have the freedom to speak her mind of what she was against. I think people need to step back from trying to act as god and control their lives. The freedom of speech and expression is one of the greatest things that we, as a country, have. How many countries out there can you get arrested for speaking out in public on an issue. The first amendment is such a great thing but it needs to hold true for all. If something is censored it is as if the government is playing favorites and if that holds true then we are not a free country at all. For everyone out there who is against censorship I have just one more thing to say to all of you...
Monday, January 13, 2020
Concept of Demolition Man Essay
* The Hollywood film represents the danger of globalization and cultural and environmental homogeneity, standardization and sanitation. * Friedman argues that because globalization is creating a single marketplace, it is homogenizing consumption and culture and can run the risk of wiping out ecological and cultural diversity throughout the world. In the Cold War system, cultures didnââ¬â¢t interact as frequently or directly as they do today, where they are often offered up for global competition and comparison against one another. Diversity in Globalization * Friedman argues that because globalization is often associated with Americanization, countries need to develop strong cultural and environmental filters so they can interact with but not be overwhelmed and swallowed by the herd. He suggests the most important filter is the ability to ââ¬Å"glocalize,â⬠meaning a cultureââ¬â¢s ability to absorb natural influences into their culture yet reject those that are alienââ¬âto assimilate aspects of globalization into your culture in a way that adds diversity without overwhelming. * Globalization will be sustainable as long as we manage these filters in a way that protects our culture while simultaneously getting the best out of othersââ¬â¢ cultures. Methods for Greening Globalization * Mobilize the environmental entrepreneursââ¬â term coined by Keith Algers for an organization meant to stop the logging activities in the rainforest in Brazil while formulating a plan to avoid unemployment among these loggers. Looking at the bigger picture, it implies finding solution to the growing problems of compromise in the industrialized society that environmental protection and economic development can coexist together. * Environmentally Sound Production Methods ââ¬â Corporations and shareholders should be pressured by the government to adapt new environmental policies. The government hitting companies over the head with both new regulations and new tax incentives to be green, and with SFC telling companies they have to start accurately portraying their environmental liabilities to shareholdersââ¬âsuch as where they are being sued for dumping and what the cleaning up costââ¬âthere has been a paradigm shift. * Learning how to use globalization itself. Where globalization is an asset is in the fact that it is creating ââ¬Å"Super-empowered environmentalistâ⬠, who are acting on their own, can now fight back rather effectively against both the Electronic Herd and governments. Thanks to the Internet, environmentalists in one country are quickly relaying how a multinational behaves in their country to environmentalists in other countries. Preventing cultural homogeneity * GlocalizationHhlksal;kl;ksdsl;adkls;adkals;dââ¬âthe ability of a culture, when it encounters another strong cultures, to absorb influences that naturally fit into and can enrich that culture, to resist those things that are alien and to compartmentalize those things that, while different, can nevertheless be enjoyed and celebrated as different. * Unhelathy Glocalizationââ¬âwhen you absorb something that isnââ¬â¢t part of your culture, doesnââ¬â¢t connect with anything latent in your culture, but you have so lost touch with your culture, you think it does. * Glocalism alone is not sufficient to protect indigenous cultures from globalization. Some hard filters are also needed. To begin with you need zoning laws, protected area laws and educational programs to preserve unique regions and a cultural heritage from insidious homogenous development.
Sunday, January 5, 2020
A History of Napoleons Continental System
During the Napoleonic Wars, the Continental System was an attempt by French Emperor Napoleon Bonaparte to cripple Britain. By creating a blockade, he had planned to destroy their trade, economy, and democracy. Because British and allied navies had impeded trade ships from exporting to France, the Continental System was also an attempt to reshape the French export market and economy. Creation of the Continental System Two decrees, that of Berlin in November 1806 and Milan in December 1807 ordered all allies of France, as well as all countries who wanted to be considered neutral, to cease trade with the British. The name ââ¬ËContinental Blockadeââ¬â¢ derives from the ambition to cut Britain off from the entire continent of mainland Europe. Britain countered with the Orders in Council which helped cause the War of 1812 with the USA. After these declarations both Britain and France were blockading each other (or trying to.) The System and Britain Napoleon believed Britain was on the verge of collapse and thought damaged trade (a third of British exports went to Europe), which would drain Britainââ¬â¢s bullion, cause inflation, cripple the economy and cause both a political collapse and a revolution, or at least stop British subsidies to Napoleonââ¬â¢s enemies. But for this to work the Continental System needed to be applied for a long time over the continent, and the fluctuating wars meant it was only truly effective in mid 1807-08, and mid 1810-12; in the gaps, British goods flooded out. South America was also opened to Britain as the latter helped Spain and Portugal, and Britainââ¬â¢s exports stayed competitive. Even so, in 1810-12 Britain suffered a depression, but the strain didnââ¬â¢t affect the war effort. Napoleon chose to ease gluts in French production by licensing limited sales to Britain; ironically, this sent grain to Britain during their worst harvest of the wars. In short, the system failed to break Britain. However, it did break something else... The System and the Continent Napoleon also meant his ââ¬ËContinental Systemââ¬â¢ to benefit France, by limiting where countries could export and import to, turning France into a rich production hub and making the rest of Europe economic vassals. This damaged some regions while boosting others. For instance, Italyââ¬â¢s silk manufacturing industry was almost destroyed, as all silk had to be sent to France for production. Most of the ports and their hinterlands suffered. More Harm than Good The Continental System represents one of Napoleonââ¬â¢s first great miscalculations. Economically, he damaged those areas of France and his allies which relied on trade with Britain for only a small increase in production in some areas of France. He also alienated swathes of conquered territory which suffered under his rules. Britain had the dominant navy and was more effective in blockading France than the French were in trying to cripple Britain. As time passed, Napoleonââ¬â¢s efforts to enforce the blockade bought more war, including an attempt to stop Portugal trading with Britain that led to a French invasion and the draining Peninsular War, and it was a factor in the disastrous French decision to attack Russia. It is possible that Britain would have been harmed by a Continental System that was properly and fully implemented, but as it was, it harmed Napoleon far more than it harmed his enemy.
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