Temperature On The Growth And Survival Of Bacteria Biology Essay

Temperature On The Growth And Survival Of Bacteria Biology Essay Abstract: The aim of this experiment was to asses the growth and survival of 5 bacteria. The method involved placing each of the bacteria in water baths of various temperatures for certain periods of time, taking them out and placing them in their optimum temperatures and monitoring their growth/survival rate over the course of the week. The results obtained showed that how well the bacteria grew after they had been placed in their optimum temperatures and left for a week. From this it was concluded what the temperature class of each bacteria was. Introduction: The objective of the experiment was to look at the growth and survival rate of 5 bacteria namely, Bacillus stearothermophilus, Escherichia coli, Enterococcus faecalis, Bacillus subtilis and Pseudomonas fluorescens. Escherichia coli, commonly referred to as E.coli is a gram negative bacterium which is rod shaped. It is usually found in the large intestine of warm blooded animals. It is also found in foods and water. It is a facultative aerobe meaning that O2 is not necessarily required for growth but is preferred for better growth thus it is able to metabolise both aerobic and anaerobically. Every microorganism has a minimal, optimal and maximal temperature. These are known as cardinal temperatures and they tell us a lot about the nature of a microorganism. A mesophile is an organism which grows at its best in medium temperature conditions. A psychrophile on the other hand is an organism which is capable of growing in extremely cold temperatures. Thermophiles are virtually the opposite of psychrophiles. Theyre organisms which are capable of growing and reproducing the hot environments. The term thermophile means that it is heat loving or heat tolerant. The temperature and pH are good indicators of the environment E.coli can be found. The fact that it has a ph of 6-7 means that it is found in mildly acidic to neutral places which explains why it is in the large intestine of mammals. The bacteria manage to survive in these various environments due to their adaptive metabolism. (Madigan, Martinko, Dunlap and Clark, 2008). Enterococcus faecalis (E.faecalis) is a gram positive and is naturally occurring in the intestine of mammals, the soil, in plants and in water. The presence of E.faecalis and E.coli in the water is usually an indication that the water has been contaminated. It is found in similar habitats to E.coli. Bacillus stearothermophilus (B.stearothermophilus) is also a rod shaped gram positive organism it is usually found in hot springs and the soil. Pseudomonas fluorescens (P.fluorescens) is a gram negative rod shaped bacterium. It is usually found in cooler environments such as water. It is an obligate aerobe which means that it cannot grow in the absence of oxygen. Bacillus subtilis (B.subtilis) is also a rod shaped gram positive bacterium which is mainly found in the soil. It too is an obligate aerobe (Brooker, Widmaier, Graham and stilling, 2007). Method: Please refer to the schedule for this. Results: Below are the tabulated results that were obtained from the experiment. Table 1 shows the effect of inoculating the bacteria at different temperatures had on their growth rate. Table 2 shows the results of exposing the bacteria to extreme heat conditions on their survival rate. Temp (Â °C) 25 37 42 55 E.coli +++ +++ +++ ++ +++ +++ +++ +++ +++ +++ ++ ++ E.farcalis +++ +++ +++ +++ +++ +++ +++ ++ +++ +++ +++ + B.subtilis ++ +++ ++ ++ +++ +++ +++ ++ +++ +++ +++ +++ P.flourescence ++ +++ +++ ++ ++ ++ B.steaothermophilus + + + ++ + ++ +++ + The table above shows how well the bacteria grew at different temperatures. Really strong growth is represented by +++, medium by ++, slow growth by + and no growth by -. Looking at E.coli for example it is clear that it only grows well in the region of 25-42Â °C anything beyond this showed absolutely no growth occurring. Time (minutes) E.coli Temp (Â °C) 0 2 5 30 90 40 Y, N, Y Y, Y, Y Y, Y, Y Y, Y, Y Y, Y, Y 60 Y, Y, Y Y, Y, Y Y, Y, Y N, N, N N, N, N 80 N, Y, Y N, N, N N, N, N N, N, N N, N, N 100 N, N, Y N, N, N N, N, N N, N, N N, N, N B.subtilis 40 Y, Y Y, Y Y, Y Y, Y Y, Y 60 Y, Y Y, Y Y, Y Y, Y Y, Y 80 Y, Y Y, Y Y, Y Y, Y Y, Y 100 Y, Y Y, Y Y, Y Y, Y Y, NTable 2: The effect of heat on survival of bacteria. Key: Y= growth present N= no growth E.faecalis 40 Y Y Y Y Y 60 Y Y Y Y N 80 Y Y Y N N 100 Y Y Y N N B.stearothermophilus 40 Y, N Y, N Y, N N, N N,N 60 Y, N N, N N, N N, N N, N 80 N, N N, N N, N N, N N, N 100 N, N N, N N, N N, N N, N P. fluorescens 40 Y, N, Y Y, Y, Y Y, Y, Y Y, Y, Y Y, Y, Y 60 Y, Y, Y Y, Y, Y Y, Y, Y N, N, N N, N, N 80 N,Y, Y N, N, N N, N, N N, N, N N, N, N 100 N,Y,N N, N, N N, N, N N, N, N N, N, NDiscussion: With the information that is in table 1 the nature of each bacterium can be established. E.coli showed exceptionally strong growth in the range of 25 to 42Â °C. These results are perfectly in line with the characteristics of a mesophile as such it is safe to assume that E.coli is a mesophile. This also explains why it is found in the human intestine. The core temperature of the human body is 36.8Â °C Â ± 0.7 which according to the literature is the optimal temperature of E.coli. The same thing goes for E.faecalis. It too is a mesophile and one of the locations where it is found is also the gastrointestinal tract. The information in table 1 coupled with the fact that it is found in the same location as E.coli means that it too has the same optimal temperature as E.coli. B.subtilis grew throughout all the temperature ranges but grew the best in 55Â °C. It was however strange to see it grow in the areas of 25-37Â °C as it is by nature a Thermophile. The minimum temperature that is required for thermophiles to grow is approximately 42Â °C. B.stearothermophilus on the other hand showed a classic example of a thermophillic bacterium. It grew best at 55Â °C. The last bacterium in table 1 was P. Fluorescens. It grew well at 25Â °C but seemed to be decreasing quiet substantially at 37Â °C. The information on the table did not quiet fit in with the characteristics which are exerted by mesophiles. Mesophiles usually grow best at around 30-40Â °C however P.fluorescens optimal temperature was around 25Â °C which meant that it could not be a psychrophile. It did however fit the characteristics of a psychrotroph. Psychrotrophs are organism which grow at 0Â °C i.e. similar to psychrophiles but, usually have an optimum temperature of 25Â °C whereas psychr ophiles have and optimum temperature of 10-12Â °C (www1). Table 2 showed the effects of exposing the bacteria to high temperatures had on their survival. Temperature is most likely the most important factor that contributes to the growth and survival of the bacteria. From the literature it can be gathered depending on the organism, exposing it to very high temperatures will kill it. In the case of E.coli this is the case. It managed to stay alive at 40Â °C for 90minutes. This is understandable as this is below its maximal temperature. Once it had been placed into higher temperatures for a long enough duration, it died off. This was not the case for B.subtilis. It proved to be growing throughout all temperature ranges for the full 90 minutes of the experiment. The fact that it managed to survive at temperatures as high as 100Â °C implies that it may be a hyperthermophile (Madigan, Martinko, Dunlap and Clark, 2008). P. fluorescens also died off after being exposed to increased temperatures for some time. At 30 and 90 minutes, all of people who were doing the experiment reported that there were no bacteria alive at 60Â °C. At 2 minutes into the experiment at 80 and 100Â °C none of the bacteria were alive. Most of the results obtained from the experiment seemed to be in line with the information found in the literature some werent for example E.faecalis was still alive in almost all of the higher temperature ranges when clearly it shouldnt have been as it was is a mesophile and shouldnt grow after around 46Â °C. B.stearothermophilus, a thermophile was not growing in temperature ranges where it should have been. These mistakes may have been due to applied correct aseptic techniques while inoculating properly. In order to eliminate such errors the experiment could be run 2 to 3 times.

A High Wind In Jamaica :: essays research papers

  Ã‚  Ã‚  Ã‚  Ã‚  A High Wind in Jamaica is set in The Caribbean during the mid-1800’s. The book is about a group of children living on a pirate ship, and gives insight into the world that children live in. Over the course of the book, the children do many bad things, without feeling any guilt: Emily murders a man; Rachael drops a marlin spike from the mast almost killing Emily, and Emily condemns the captain and crew that she had come to love to death or deportation without seeming to care at all.   Ã‚  Ã‚  Ã‚  Ã‚  At the beginning of the story Emily is just an ordinary little girl, but as the story continues she begins to feel herself changing. By the end of the story, Emily has gained self-consciousness and thinks of herself not as an ordinary little girl but as â€Å"Emily†. Emily murders a captured Dutch captain, but she doesn’t feel guilty and no one suspects that she did it. She only worries that she might be found out. She didn’t even think that what she did was wrong:   Ã‚  Ã‚  Ã‚  Ã‚  Near the end of the book, Emily is brought to court to testify against the pirates. When asked about the murder of the Dutch captain, she cries â€Å"†¦He was all lying in his own blood†¦he was awful! He†¦he died.† Sobbing hysterically, Emily is carried out of the box by her father. â€Å"As he stepped down with her she caught sight for the first time of Jonsen and the crew†¦The terrible look on Jonsen’s face as his eye met hers.† Once she is safely in a cab, â€Å"she [becomes] herself with surprising rapidity†. â€Å"She began to talk about all she had seen, just as if it had been a party†¦Ã¢â‚¬  All Emily worries about is whether or not â€Å"she said her piece properly†.   Ã‚  Ã‚  Ã‚  Ã‚  Near the end of the book, Captain Jonsen decides to put the children on a steamer to England. Before they are sent to the new ship, he asks them not to tell anyone that he and the crew are pirates. Everyone agrees not to tell, and it seems that all is well. When the children arrive on the steamer, they do not say anything about their stay on the pirate ship. When Emily becomes hysterical a stewardess carries her down to her room. While she is being put to bed, she tells the stewardess about the pirates, breaking her promise to Jonsen, Emily thinks nothing of it, and she feels relieved at having told someone.

Reading Reflection Essay

The literary work that we discussed this week was interesting to me in so many ways. The chapters talked about different types of literature such as poems, short stories, and also novels. Throughout the reading I experience literature in a way I have never understood before. Literature restores the past, stimulates the imagination, glorifies the commonplace, evokes emotions and links feeling to thinking, upholds a vision of the ideal and reveals human nature by exploring significant human questions. I have to say I have been truly convinced. The purpose of the creative process is to give things form. Writers are artists who use words to express ideas and feelings. As a reader I had to use my imagination which is the human power that shapes artistic expression; it enables a writer’s work to become an expression of meaning in our world, and allows readers to engage in identifying with what the writer’s work has to say about things that matter. So basically we all become writer’s in a sense. When reading this paper you imagine how to feel when I found out a little more about literature. Literature allows you to read with a purpose while at the same time using the experience to connect to the writer. Literature is a creative process that begins in writers’ experiences and imaginings. Image is a distant representation of something that can be experienced and understood through the senses or the representation of an idea. Writer’s use precise language in developing images, or imagery in a literary work. Tone also plays an important part in a literary work. It identifies how the author approaches a subject and conveys it to readers. Either way we look at it as literature been a very important part of our history. We tend to use literature in everyday life. We have to search for meaning and explore literature in different aspects of been a reader or writer. We can use the Biographical/Historical approach to evaluate the meaning of a literary work. It’s the attempt to measure the extent to which the life of the author or a historical context can shape literary expression. Critics’ adopt a historical period as a context, creates characters that reflect its value, and explores trends that occur in it. William Faulker was an American writer who took this approach, creating narratives that identified values and conflicts in a historic era in the South. He created complex characters and a community that carefully mirrored life in the South and, used them as centerpieces in several of his works. You could also apply persona to this analytical approach referring to the narrator in a story or the speaker in a poem, who may or may not reflect the perspective of the author. The creativity to start a literary work is in our imagination we just have to put it down on paper. Reference: Clugston, R. W. (2010). Journey into Literature. San Diego, California: Bridgeport Education, Inc. https://content. ashford. edu/books Ashford Online Library.

The Summary Of Getting Past No Essays - Negotiation, Free Essays

The Summary Of Getting Past No Essays - Negotiation, Free Essays The summary of "Getting Past No" (0) Introduction Each of us has to face tough negotiation with an irritable spouse, an ornery boss, a rigid salesperson, or a tricky customer. Under stress, even kind, reasonable people turn into angry, intractable opponents. In order to reach a mutually satisfactory agreement in an efficient and amicable fashion, this book introduces us the strategy of breakthrough negotiation. The breakthrough strategy is counterintuitive: it requires us to do the opposite of what we might naturally do in difficult situations. In addition, the essence of the breakthrough strategy is indirect action. Rather than trying to break down opponent's resistance, we make it easier for him to break through it themselves. In short, breakthrough negotiation is the art of letting the other person have our ways. (1) STEP ONE: Don't React \ Go To The Balcony The first step we need to do in dealing with a difficult person is not to control his behavior but to control our own. Because when we react-act without thinking, we usually neglect our interests. "Going to the balcony" means distancing ourselves from our natural impulses and emotions. From the balcony we can calmly evaluate the conflict, think constructively for both sides, and look for a mutually satisfactory way to resolve the problem. One the balcony, the first thing we need to do is figure out our interests. We also need to identify our BATNA- our Best Alternative To a Negotiated Agreement. The agreement must satisfy our interests better than our BATNA could. Our BATNA should be our measuring stick for evaluating any potential agreement. Often we do not even realize we are reacting, because we are too enmeshed in the situation. Therefore, we need to recognize the tactic. Make a mental note when we detect a possible trick or subtle attack. By naming the game, we are able to neutralize it easily. Once we have named the game and stop our immediate reaction, the next step is to buy ourselves time to think-time to go to the balcony. Use the time to keep our eyes on the prize-an agreement that satisfies your interests, certainly better than our BATNA can. Instead of getting mad or getting even, concentrate on getting what we want. This is what going to the balcony is all about. (2) STEP TWO: Disarm Them \ Step To Their Side Before we can discuss the problem with the opponent, we need to disarm him. The secret of disarming is surprise. To disarm our opponent, we need to do the opposite of what he expects: step to his side, listen to him, acknowledge his point, and agree wherever we can. Listening requires patience and self- discipline. Instead of reacting immediately or plotting our next step, we have to remain focused on what our counterpart is saying. Listening gives us a chance to engage him in a cooperative task-that of understanding his problem. It makes him more willing to listen to us. After listening to our opponent, the next step is to acknowledge his point. Acknowledging the opponent's point does not mean that we agree with it. It means that we accept it as one valid point of view among others. The next step is to agree wherever we can. It is hard to attack someone who agrees with us. (3) STEP THREE: Don't Reject \ Reframe Instead of rejecting our opponent's position, we need to direct his attention to the problem of meeting each side's interests. Reframing works because every message is subject to interpretation. It means putting a problem-solving frame around our opponent's positional statements. A problem-solving question focuses attention on the interests of each side, the options for satisfying them, and the standards of fairness for resolving differences. Rather than trying to teach him ourselves, let the problem be his teacher. (4) STEP FOUR: Make It Easy To Say Yes \ Build Them A Golden Bridge At last we are ready to negotiate; however, our opponent may stall. Instead of pushing our opponent toward an agreement, we need to do the opposite. Our job is to build a golden bridge across the chasm. Building a golden bridge means making it easier for our opponent to overcome the four common obstacles to agreement: it means actively involving him in devising a solution

When the Professor doesn’t show up Professor Ramos Blog

When the Professor doesn’t show up

International Business Strategies in Action Assignment - 2

International Business Strategies in Action - Assignment Example McDonald’s decided to penetrate the Chinese fast food market in the year 1992 by establishing the company’s store in Shenzhen and later in Beijing which was the world’s largest fast food retail outlet owned by the company. The objective of McDonald’s in expanding internationally was evidently to attain competitive advantage in the international market gaining the opportunities rendered by other economies such as China. For instance, China has been witnessed to be one of the fastest growing economies in terms of population, customer demand and technology since the 1990s. It is in this context that DeWit & Meyer stated the organisational purpose or mission to play a significant role in influencing the internationalisation strategies of a company. The organisational purpose of McDonald’s is depicted through its mission statement, i.e. â€Å"Plan to Win†. Through its mission statement, the company has always focused on deriving superior customer satisfaction, sustainable growth, along with the continuous development of its operations and enhancement of customers’ experiences as competitive advantages.... atement, the company has always focused on deriving superior customer satisfaction, sustainable growth, along with the continuous development of its operations and enhancement of customers’ experiences as competitive advantages (McDonald’s, 2011). However, in relation to McDonald’s entry in China, the prime objective of the company can be witnessed to attain a competitive advantage in terms of differentiation with due concern to the increasing competition of the global market. For instance, McDonald’s in its entry strategies fundamentally focused on the consumer demand of China in relation to American fast food items with the sole intention to differentiate its products from that of its competitors not only in the Chinese market but in the global market as well (Luo, 2000). Therefore, it was quite likely that the entry strategies adopted by the company were likely to be influenced by the external environmental factors of the then Chinese economy. 3.0 Situa tional Analysis: PESTLE Analysis of China 3.1 Political Environment In the early 1990s, the political system of China was recorded to be under significant change from the Confucian statecraft towards Marxism point-of-view. It was during this period that the Chinese economy was concentrating on mobilisation and was opening up to the external world that in turn gave rise to various political issues (Shambaugh & Et. Al., 2000). 3.2 Economic Environment China’s growth during the period was observed as outstanding in the global market. During the 1990s, China witnessed rapid growth in terms of its Gross Domestic Product (GDP) earning as depicted in the chart below. Figure 1. China’s GDP in 1990s Source: (Flores & Et. Al., 2003). However, the GDP growth rate of the economy was observed to be highly fluctuating

Significance of Mehmet Ali Essay Example | Topics and Well Written Essays - 2500 words

Significance of Mehmet Ali - Essay Example Most important decisions that Mehmet Ali took, were regarding the reformation of Egyptian society based on European patterns. He brought up the idea of Bureaucracy which separated Egyptian social system from the earlier patterns where Kings were very much the final authorities and every smaller decision would make sure that it takes place according to the pattern that would have pleased the king. Although, Mehmet Ali’s pattern of Society was not like a democratic system yet it made the state very powerful as it almost bound producers to sell the entire outcome to the state that will take care of reselling. Such authority of State helped Egypt to develop faster because Khedive himself would take care of revenues contrasting to modern communist systems where State is provided with power but restricts liberal policies for traders outside the state. This system turned Egyptian society and politics into a self-regulating society which paid very much for the future development in ec onomy and army. On the other hand, Mehmet Ali also rebuilt the army structure based on different segments controlled by separate department united as whole army under Khedive. It was more structured pattern compared of any military system Egypt has seen before. Consequently, Mehmet Ali also succeeded in ruling a bigger land that any earlier king of Egypt could manage to. Mehmet Ali had been a successful emperor for a long time, succeeding to establish his dynasty to work for future and to take Egypt towards the upcoming new era of modernism (Vatikiotis, 1991, p.70). Even after such a long rule over Egypt, Mehmet Ali was considered as a Turk by a number of natives. Further, progression of revolutions had been paid by this fact on large amount. Another charge revolutionaries had against Mehmet Ali’s dynasty was about their conceiving the state in limited bureaucratic structures providing no liberty for producers. However, as this fact comes up as a truth during modern society, it has paid much in Egypt’s development in earlier times. Still when it did not fit into a changed world prone to democracies, Egypt also demanded liberty and further Mehmet Ali’s dynasty led to its terminal with the revolution. Portrait of Omai- By Sir Joshua Reynolds One of the cult figures of simultaneous time of painting art is the portrait of Omai by Sir Joshua Reynolds. It holds significance as an artifact as well as a representation of Egyptian culture to the western civilization. Joshua Reynolds is known wildly among the most recognized landscape painter. In his portrait of Omai, he has used an authorized technique of expression which comes out as one of his greatest portraits. Reynolds has painted certain number of portraits of Omai which are considered on different aspects. However, best knows of his portraits of Omai is the one that was shows at Royal Academy at 1776. It has achieved a cult status in Landscape painting. Some earlier portraits painted by Reyn olds are considered previous attempt as appears that Reynolds himself was not satisfied with the outcome and wanted to make it grand. (Connaughton, 2005) Specific importance of Omai is as an encounter between East and west. It is the background of Omai’s visit to London.