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Science
Many elderly people suffer from a disease called Alzheimer's. The disease effects the brain in many ways. It slowly destroys brain cells and consequently people forget things and think and behave in different ways (Alzheimer's). There is usually no pattern for the way that that Alzheimer's attacks brain cells. "That's why a construction worker may still know how to drive a dump truck, but may not remember his wife's name" (Medina 22). The effect that Alzheimer's has on the brain causes people to behave and think in very unusual or unexpected ways and it changes their moods and personalities. My grandpa, who suffered from Alzheimer's, has displayed many of these unusual behaviors throughout the course of his disease. One behavioral problem is getting lost and confused. A person with the disease may suddenly not know where he is (Medina 28). My grandpa got up one night to go to the bathroom, and must have forgot where he was, or where he was going, because he urinated in a kitchen drawer instead of the toilet. People with Alzheimer's might have the desire to wander, which can be both dangerous for the person suffering from the disease, and frightening for family and friends. A person may wander out of his or her own house because they are unhappy with where they are living; or they may wander from room to room, with no particular purpose (Medina 28). While my family was getting together for an Easter celebration, we suddenly realized that my grandpa was not there. We searched frantically around the neighborhood, and finally found him down the road, confused. Alzheimer's may cause people to have trouble expressing their feelings (Medina 28). Many times my grandpa would try to tell us something. He often mumbled and used his hands to try to express what he...
pages: 3 (words: 731)
comments: 0
added: 11/13/2011
"Alzheimer's disease is a progressive disease of the brain that is characterized by impairment of memory and a disturbance in at least one other thinking function" (Bronstein & Pulst, 2003). When we hear about Alzheimer's disease we automatically think of older people. This is because this disease most often occurs in adults after the age of 65. Statistics show that one in eight individuals will have Alzheimer's after they reach age 65 (Cavanaugh & Blanchard-Fields, 2002). Alzheimer's disease is a form of dementia, which is any medical condition that affects the brain (Cavanaugh & Blanchard-Fields, 2002). A diagnosis of Alzheimer's is said to be a "diagnosis by exclusion" (Bronstein & Pulst, 2003). This means that there is no certain test just for Alzheimer's, but many tests that rule out other diseases. The early stages deal with short-term memory loss. Examples of this include forgetting to turn off the stove, forgetting what medications were taken in a particular day, or forgetting which medications need to be taken. As the disease progresses there is more visibility in the declines in abstract thinking and intellectual function development (Bronstein & Pulst, 2003). As the disease enters the final stages, individuals become very confused and disorientated. At this point the individual's health status has become severely deteriorated and this can cause them to develop pneumonia or other illnesses that may lead to death. Consequently, most people do not die from Alzheimer's, but other health related problems. Alzheimer's disease can last anywhere from six to eight years, however it can be present without obvious symptoms for two to twenty years. The on-set of Alzheimer's disease is very slow (Bronstein & Pulst, 2003). There are many factors that play a role in the cause of Alzheimer's disease. This disease is also genetic—a person that has family members with the...
pages: 6 (words: 1473)
comments: 0
added: 09/19/2011
The Earth formed when the sun and its forming of planets formed when a cloud of dust and gas condensed 4.6 billion years ago. In large areas, iron sinks to the center forming the core. The Mantle is made up from primarily of the minerals olivine and pyroxene. It takes up 80% of the planet. The oceanic crust typically differ from continental crust because Earth's surfaces cooled below 100 degrees C. Water rained out of the atmosphere. Continental Crust is very thicker then the oceanic crust. The oldest rock that was found on Earth was the Acasta Gneiss from the Canadian Shield. Quartz pebble formed 3 billion years ago but the zicron crystals are 4.276 billion years old. It undergoes uplift, erosion, and growth. The age of the earth was being solved in many different ways. In the 1700's they believed on the age by parts written in the bible, to getting seashells and fossils. In the 1800's for using studies of rocks to estimated earth's age. 1900's looking at meteorites and rocks by using new technologies. Ice Core are 3 meters in lengths to form a core that penetrated through the entire 3022 meter thick Greenland Ice Sheet. Left core sample depth is 2708 meters in 88,670 B.C. Middle core sample depth is 1689 meters in 10,075 B.C. The right core depth is 1325.5 meters in 5,671 B.C. Solar radiation warms the Earths surface. Some of the hear radiated back to the atmosphere. It is trapped by greenhouse gases, without it, the Earth's average temperature would be below freezing. With it planet is warm to support life. Earth's temperature is changed because of the rotation of the planet and the rotation of the storms which can follow the planet and the areas of different climates. That climate changed effect through...
pages: 4 (words: 953)
comments: 0
added: 02/06/2012
Amino Acids Introduction This lab was done in order to detect the presence of amino acids. Amino acids are distinguished from other biomolecules because not only do they contain carbon, hydrogen and oxygen, but nitrogen as well. The Amine group (NH2) is where the nitrogen is located. Amino acids contain two other groups, one is called the Carboxl group (COOH) and the other is called the variable "R" group. The "R" group is what makes amino acids different from one another. All of these groups are connected to what is called the "central" carbon. They also combine with one another in a line. These combinations are called polypeptides. The carboxyl group of one amino acid connects to the amine group of the other. These connections or "bonds" are called peptide bonds (abbr C-N) and are the building blocks for proteins. Material and Methods Graduated cylinder (10ml)(2) testubes(14) waxpencil Chromatography chambers test tube rack benedict reagent Plastic metric ruler test tube brush 2.5% NaOH reagent 10 µl micro capillary tubes hair dryer Liquid soap SA TLC sheets chromatography solvent Procedures A. First we obtained a sheet of Ninhydrin thin layer chromatography (TLC). The chromatography chambers where already set up for us with 50 ml of protein chromatography solvent at the base and 15 ml in the saturation pad. We then drew a line across the bottom of the TLC sheet, about 2 cm above the edge. We split the line into 13 vertical segments 1 cm from the edges and 1.5 cm in between, numbered and labeled them according to their samples. A line 10 cm above the first horizontal line was then drawn. 1. glutamic acid 6. arginine 11. hydrolyzed casein 2. praline 7. glycine 12. beef broth 3. tyrosine 8. urea 13. milk 4. cysteine 9. biuret 5. alanine 10. casein Thirteen microcapillary tubes were obtained; each one was used to place drops of each...
pages: 3 (words: 760)
comments: 0
added: 09/14/2011
Index 1. What is an amphibian? 1.1 What is an ectotherm? 1.2 Diversity 1.2.1 Anura 1.2.2 Caudata 1.2.3 Apoda 2. What is an amphibian like? 2.1 Structure 2.2 Appearance 3. How does an amphibian live? 3.1 Feeding Process 3.2 Reproduction 3.3 Adaptations 3.3.1 Respiration 3.3.1.1 Obligate Aerobes 3.3.1.2 Obligate Anaerobes 3.3.2 Endospores 4. Importance 4.1 Ecological 4.2 Economical Amphibians What is an amphibian? The word amphibian comes from the Greek word 'amphibios' which means two lives: amphibians have a larval stage and an adult stage that are usually very different from each other. They are vertebrates, have thin, moist skin and four legs. They have no claws under toes. Nearly all of them rely on water for reproduction. What is an ecotherm? Amphibians are most common in regions that have warm temperatures all year because they are ecotherms. An ecotherm is an animal in which the body temperature changes with the temperature of its surroundings. During such times, many amphibians burrow into the mud and stay there until suitable conditions return. Amphibians diversity They are classified and divided in 3 groups: • Anura – frogs and toads belong to this group, they are amphibians without tail. All adult frogs and toads eat insects. Some frogs and toads produce toxins, they can kill predators; they also have vocal cords that are capable of producing a wide range of sounds. They spent part of their life cycle in water and part on land. • Caudata – salamanders belong to this order. A salamander has long, slender body with a neck and tail. They resemble lizards but have smooth, moist skin and lack claws. They range in size from a few centimeters up to a size of 1.5 meters. Some are aquatic, and others live in damp places on land. • Apoda – Caecilians are limbless amphibians. Caecilians are amphibians that have no limbs, with a short, or no, tail. Caecilians are primarily tropical animals with small eyes that are often blind. They eat...
pages: 6 (words: 1395)
comments: 0
added: 01/29/2012
Fish Cheeks Critique Amy Tan, a Chinese-American writer, was born in Oakland, California in 1952. In 1989 she wrote The Joy Luck Club, her first novel which tells of the relationships and struggles between full Chinese mothers and their Americanized Chinese daughters. Although the story was fiction, most of the experiences came from Tan's real life. Besides The Joy Luck Club, Tan has written three more successful novels. Amy Tan's "Fish Cheeks" is a short narritive about when she was a little girl and her crush came over for dinner. But it was much more than that. "Fish Cheeks" is a reflection of differences in culture, pride, shame, and realization. One Christmas Eve, Amy's parents invite her crush Robert, and his family over for dinner. Amy isnt particulary happy about this because Robert and his family are white while she is Chinese. Obviously the Tan's Christmas dinner would be much different than what Robert's family was used to. During the meal, Amy was embarrased about how her relatives displayed their Chinese customs in front of their guests. After dinner her mother told her that she should never be ashamed of her culture and her only shame was to have shame. "Fish Cheeks" relates to todays society in many ways. With the growing population of multi-cultural children, there are bound to be some who are confused about where they fit in, in society. Since Robert is white, Amy wants to be as similar to him as possible so she is ashamed of her Chinese heritage. This is not the way to be. You should always have pride in your culturen no matter what anybody else thinks. "Fish Cheeks" was a good story overall. Although the characters were not developed well, they didnt have to be. The story was short, simple, and to the point, with...
pages: 2 (words: 358)
comments: 0
added: 02/16/2012
Amylase and Starch experiment We took 3 trays, the name for the trays I have forgotten but they had about 12 small craters in each. We put a couple of drops of iodine into each crater. Then we took a syringe and filled it up to the 10 mark with starch solution, then, with the same syringe we sucked up a further 5 of amylase. We took a stopwatch and every 30 seconds we put a drop from the syringe into one of the craters and recorded the colour. To begin with, the resultant colour was black, indicating a high presence of starch. This is no surprise, the syringe was 2/3rds full of it. However, after about 5 minutes of this, we noticed that the colour was getting lighter. The black became a dark brown, which then became a light brown and got ever lighter until Mr Bishop told us to stop the experiment. From this we can see that the starch level dropped considerably the more time we gave it, we can conclude that Amylase is a starch digesting enzyme. Then we repeated the experiment, but with a difference. Into the usual syringe we added a large amount of salt as well. This created a huge difference, no sooner had we put a drop into the iodine, most of the starch had already gone and our first reading was not black as before but light brown. The colour got lighter and lighter at a very fast rate until there was almost no starch at all. From this we can see that the presence of salt makes Amylase digest starch faster. This could be for one of two reasons, either the salt itself breaks up the starch or the salt stimulates the active sites on the amylase enzymes. The second of...
pages: 4 (words: 974)
comments: 0
added: 01/14/2012
The life expectancy at birth is the age in which an individual is expected to reach when they are born. The life expectancy varies across nations and continents and there may be a number of reasons for these variations. It is important that we become educated about positive and negative factors that are influencing life expectancy across countries so changes can be implemented. If we can begin to understand why life expectancy varies for different nations and why life expectancy is where it is today, we will be able to do a better job raising the living standards for all people in the future. The purpose of this study is to answer the underlying question: What are some factors that influence life expectancy across nations? Model Construction The data in this study was obtained from the U. S. Census Bureau, International Programs Center, International Database. This study looks at two models that use cross-sectional data that was taken from 39 countries. There were three unusual observations within the data, one observation whose x value gave it a large influence and two observations with a large standardized residual. These observations were not omitted. The data is from 1999. The dependent variable of interest is life expectancy at birth within each nation. The observations are in years. The independent variables for the analysis are as follows: GDP per Capita (PPP) The gross domestic product per capita (PPP dollars) for each nation was observed and regressed against life expectancy to determine if this variable had any impact on life expectancy. The purchasing power parity or PPP was used because it uses a common set of prices, those of the United States, to measure the output of each country. This provides a more accurate comparison of incomes for each country. One would expect that in countries with a...
pages: 6 (words: 1493)
comments: 0
added: 08/31/2011
An Article To Describe the Ethical Issues Involved in Using Forensic Psychology In A Court Room To firstly understand and then evaluate the importance of ethical practice in the role of forensic psychologists we must first understand what it means to be a forensic psychologist. This involves the burden put on them and the power of persuasion they weald in a courtroom when it comes to persuading jurors for or against a case. So firstly we must ask the question what is forensic psychology? It's difficult to turn on a television, go to the movies, or walk through a bookstore without running across a fictional portrayal of a crazed but brilliant serial or mass murderer being tracked by a psychologically trained and deductively sound hero. Popular movies such as Silence of the Lambs and Hannibal and television shows like CSI or MIT or something else that sounds just as thrilling, they often depict the intersection of law enforcement and psychology in a sensational and dramatic fashion. If you watch the news or read a newspaper you can hear about the psychological "profile" written up by a forensic psychologist linked to the latest serial killer/high profile case. In truth the world of a forensic psychologist is far from the glitz of popular media and lies mostly on evaluating witnesses and assessing the worthiness of a defendant to stand trial. So if someone told you they were a forensic psychologist what would you expect them to do? If like most people you automatically zoom in on the word forensic and automatically think that they help collect evidence at a crime scene or that they perform autopsies you would be far from the truth. By definition a forensic psychologist literally describes any individual who works where the legal system and psychology cross. The American Psychology-Law Society...
pages: 7 (words: 1730)
comments: 0
added: 10/14/2011
Introduction Since September 11th, terrorism has featured regularly in the media causing widespread alarm. Since the postal attacks in the winter of 2001, in which Bacillus anthracis spores were delivered by mail to targets of terrorism, attention has turned to the possibility of terrorist attack using bioweapons. Bacillus anthracis : The Organism Bacillus anthracis spores, the initial infective agent of the disease anthrax are 1-2ƒÝm by 0.5-1ƒÝm in size(3). Once implanted the spore germinates into the vegetative cell, a gram positive, facultatively anaerobic bacterium(1). These non-motile vegetative cells are 1-8ƒÝm by 1-1.5ƒÝm in size(2) and secrete three toxin components: lethal factor (LF), oedema factor (ED), and protective antigen (PA)(1) (see fig1). 1) Bacillus anthracis 2) EF PA LF 3) Anthrax: The Disease and its Treatment The disease is exhibited in three forms in humans. The most common form is cutaneous anthrax. Spores penetrate the skin via a wound, germinate and cause a temporary disfiguring oedema(7). This is harmless unless the oedema blocks an airway but has been known to lead to anthrax meningitis in some cases(1). The most morbid form is inhalational or pulmonary anthrax, which is fatal in approximately 90% of cases(7). The third, rarest form of the disease is ingestional anthrax, which is exhibited gastro-intestinally or oropharyngeally(1). This occurs due to ingestion of meat from an infected animal. This form of the disease is fatal in around 50% of cases(7). The vaccine employed in the USA is an inactivated cell free product, which is 90% effective for 1-2 years. This is currently administered to those in the military and high-risk members of the US postal service(2). B.anthracis is sensitive to a range of antibiotics, such as penicillin, ampicillin, tetracycline, erythromycin, chloramphenicol, oxacillin, streptomycin(8), vancomycin, rifampin, chloramphenicol, imipenem, clindamycin, clarithomycin. Ciproflaxin or doxycyclin, along with one or two other antimicrobial agents are administered prophylactively for 100 days after suspected...
pages: 7 (words: 1673)
comments: 0
added: 12/10/2011
Mass media communication is relevant in peoples' lives today, and caters to all age groups from young to old. Almost everyone in the United States of America, even the world, participate in the technological highway that has been rapidly advancing since the time of the light bulb. Mass, personal, and telecommunications are very apparent in my everyday life. Whether I am working out at the gym, working towards an education at school, relaxing at home, or driving to New Jersey on the weekend, I am given the opportunity to watch television, surf the web, converse with friends, and family, or listen to radio stations, and music wherever I go. I am constantly surprised on how media communications have taken the world by storm when I partake in my daily work out routine. While I am working out, I have the opportunity of using mass media communications, or telecommunications. The local gym gives me the option of listening to the city radio station, watching television, and/or talking on the phone, while working out. Televisions are mounted non-sequentially around the grounds, and above the cardiovascular equipment, to make the environment more comfortable and relaxed for me, as well as all the other patrons of the gym. Newspapers and magazines are also provided at the receptionists' desk, at the entrance of the gym, for those clients who are more comfortable reading current events while exercising. When I am at home, if I have time, I will usually kick back, and read a book that I have picked from the best seller list, or indulge in a trendy magazine that I picked up from the line in the grocery store. The times when I am "running by the clock", and have to limit the amount of leisure time I delegate myself, I might watch a television...
pages: 2 (words: 444)
comments: 0
added: 11/18/2011
ABSTRACT The predation of diving ducks on Dreissena polymorpha was investigated to determine which size of zebra mussels are most commonly preyed upon by waterfowl. The gizzard contents of various species of ducks from Point Pelee Ontario were examined for mussel shell fragments to determine the mussel size consumed. The data was compiled to calculate an average mussel size and the amount of predation on each size by ducks. Waterfowl fed preferentially on zebra mussels of moderate size with a mussel size of 16mm being optimal. The delicate balance between energy expenditure and consumed food energy along with the threat of kleptoparasitism guide waterfowl to feed upon mussels around 16mm. It is also possible that confounding variables such as fish predation have affected size selection by altering the mussel population densities in the hunting habitats. INTRODUCTION Zebra mussels, or Dreissena polymorpha, invaded the Great Lakes in 1985 from European waters. Their rapid spread throughout the lakes is believed to be a consequence of recreational boating and commercial shipping (Johnson and Padilla, 1996). Zebra mussels' abilities to attach and proliferate on several types of substrata have increased their numbers tremendously with densities reaching as high as 700 000 mussels per square meter in the most populated areas near power plants (Custer and Custer, 1997). This has resulted in both unstoppable abiotic and biotic changes (Macisaac, 1996). One of the possible opposing forces for the invasion of Dreissena polymorpha has been the predation by molluscivorous waterfowl. Zebra mussels will attach themselves readily to many submerged substrates including rock, macrophytes, native molluscs, canal and dock walls, water craft and motor outboards (Macisaac, 1996). Dreissena fouling of water intake pipes is also a noted concern and ongoing problem at various industrial plants along Lake Erie. Macisaac (1996) attributed the dense population of mussels around intake pipes to the...
pages: 2 (words: 349)
comments: 0
added: 02/03/2012
To investigate the effect of detergent on Cell Membranes Cell membranes are composed mainly of phospholipids. A cell membrane is a phospholipid bilayer, which acts as an effective barrier, controlling what substances enter and exit the cell. This property can be explained by the structure of phospholipids. Phospholipids are composed of a hydrophilic head and a hydrophobic tail. When in water, all of the hydrophilic heads face outwards into the water and the hydrophobic tails face each other, shielded on either side by hydrophilic heads As the hydrophobic tails create a non-polar interior, it is difficult for polar molecules, or ions, to pass through them and so acts as a barrier to most water-soluble substances. The phospholipid bilayer also prevents the contents of the cell from escaping. If detergent is introduced to the phospholipid bilayer it gradually breaks down, allowing the interior contents to vacate the cell, which will inevitably lead to the demise of the cell. Detergents attack lipids (for example in washing powders), which are an integral part of phospholipids, and make them increasingly soluble, thus destroying the cell membrane. Hypothesis Because of the effect of detergent on cell membranes, it is feasible to assume that the greater the amount of detergent added to the cell membrane, the greater the amount of phospholipids that will be dissolved, and therefore the greater the leakage of cell content Strategy In a previous experiment concerning the effect of heat on channel proteins in cell membranes, beetroot discs were used. Three beetroot discs were placed in each test tube and were then subjected to various temperatures. These proved to work very effectively, releasing a pink/red pigment, Betacyanin, when the channel proteins broke down. The leakage of Betacyanin was easy to see and record, and therefore beetroot discs will be used in this experiment. In this case, the beetroot discs will be...
pages: 3 (words: 763)
comments: 0
added: 02/18/2012
High Tech Talk: Analog vs Digital – Making the Conversion Primarly through the use of computers has the world been forced to digitize. We were an analog people for centuries before the advent of computers. Clocks were analog, radio frequencies were analog, and we spoke through the telephone in analog. Then came the advent of computers and we needed this new digital entity to coexist in an analog environment. Two main areas had to be converted from their analog state to digital. The area of sight and the area of sound. Sounds like the "Twilight Zone" but in reality we needed to convert pictures, both black and white and color, and sound - voice, music, and telephone communications into a form capable of being stored on a computer. The conversion of color to digital form requires the sampling of tiny areas on a picture (pixels) and coming up with a 32 bit binary number that represents one of 4 billion shades of color and then storing these binary numbers in sequential order to allow us translate them back into a recognizable image. This is performed by an analog-to-digital converter ADC (storing process) and then a digital-to-analog converter DAC (recovery process). Sound takes a similar path where the binary number of the sampled analog sound represents not color but frequency. Additional electronic circuitry in conjunction with the ADC and the DAC must be used to produce the final image or sound or both in the case of video or movies. The transmission of data over long distances must also go through a conversion process through the use of a modem (modulator – demodulator). Digital signals are converted to voice frequencies ( binary 0 – 1200 Hz, binary 1 – 2400 Hz) and then back to digital by way of the modem....
pages: 2 (words: 300)
comments: 0
added: 11/22/2011
This article is based on bipolar disorder in everyday people. Bipolar disorder is a mental illness is identified by intense and random mood swings. Most everyone effected by this illness go into relapse. This paper analyzes the research by Weisman et. al. (2002). They conducted a study on bipolar individuals, which consists of a three-element treatment. The segments include Psychoeducation, Communication Training, and Problem Solving. Weisman et. al. (2002) wanted to discover whether their treatment was effective against the disorder and, to determine if their treatment would the likelihood of relapse. Weisman et. al. (2002) hypothesized that therapists rated as less competent or adherent to the treatment protocol will have more patients relapsing within one year of entering the treatment then more competent and/or adherent therapists. They also hypothesized, that when patients did relapse, therapists greater in competence and adherence would have patients who stayed well longer had less inpatient hospitalizations. The researchers first studied the research of those recently before them, and create an effective way to completely cure bipolar disorder, by getting rid of any relapses the patients might go through. A plan was then created using the findings from their research. The researchers found and recruited participants of another study designed to assess the efficacy of a psycoeducational intervention program used in conjunction with mood-stabilizing medications in the treatment of bipolar disorder. In their study, 13 clinicians trained in FFT, provided the treatment. Participants who met the criteria included 26 families with a family member with bipolar disorder. Sixty six percent of the families had one relative in the program, and 34% had two or more relatives participating. Their ages ranged from 18-46 (average age is about 27 years old), they had an average education level of 2 years after high school, and 64% of the patients live with...
pages: 4 (words: 871)
comments: 0
added: 01/15/2012
Introduction The goal of this lab was to analyze the iron content in both iron tablets and cereal. The methods used to achieve this goal included using spectrometry to set a calibration curve and measure iron content within the mixture of cereal and the iron tablet. The absorbances of the mixtures were used in conjunction with the calibration curve to measure the amount of iron content in each. Experimental First the calibration curve was made by preparing a mixture of Fe(NO3)3 and KCSN with HNO3. The five molar HNO3 was diluted to one molar HNO3 using the formula M1V1=M2V2. One hundred milliliters of .001M Fe(NO3)3 and .1M KCSN both in HNO3 were prepared by measuring out .0403 grams of Fe(NO3)3 and .972 grams of KCSN and putting each in a flask and filling that flask to 100ml with HNO3. After these solutions are prepared 1.0ml of the iron nitrate was placed in a 250ml beaker with 100ml of the KCSN solution. A dry cuvette was filled with 1.0M HNO3 and placed in the spectrometer and the instrument was zeroed. The cuvette was then rinsed out. The solution that was previously prepared is then put into the cuvette and put in the spectrometer and the absorbance is measured. The solutions must be poured back into the original flask in order to maintain a constant volume. Next another 1.0ml of iron nitrate was added to the 100ml of KCSN solution and put in the cuvette. The absorbance was measured again and recorded. This procedure was repeated until 10ml of iron nitrate were used in the solution. After all the absorbencies were recorded the graph was plotted with iron nitrate concentration on the horizontal axis and absorbance on the vertical axis. To extract the iron from the cereal, first the 32.0grams of cereal were placed in a...
pages: 4 (words: 985)
comments: 0
added: 01/18/2012
Information on enzymes & rennin Enzymes are biological catalysts that speed up reactions without being affected so that they can be used to speed up another reaction. Enzymes are soluble globular proteins. Enzymes reduce the energy needed to make a reaction happen. This energy is known as the "activation energy". We need enzymes to stay alive, without them, the reactions in our body would take place far too slowly. Also, we need to be able to control how fast certain reactions take place, if we didn't have enzymes, all our bodies reactions would take place at different speeds. Certain poisons such as cyanide block the active site, and so stop the enzyme from working. To understand the investigation better, here is some background information on rennin. Rennin is produced inside young mammals as a way of converting caseinogen into casein. It needs to do this to absorb the precious proteins in the milk that it feeds on. Caseinogen is soluble, and is very hard to separate from water and as a result, it would not stay in the digestive system long enough to be absorbed and the mammal would die. Rennin converts the caseinogen into casein, (which is insoluble) so that it remains in the digestive system for much longer. This enables it to be broken down and absorbed into the mammals blood stream. Hypotheses on the effect of temperature As the temperature increases the rate of reaction increases as well. At a certain point the enzyme starts to be denatured which dramatically decreases the rate of reaction. The reaction we have investigated is: Caseinogen Casein More commonly known as the "curdling of milk". My graph shows that as the temperature increases, the rate of reaction increases as well. This is because as the temperature increases, each molecule of rennin and caseinogen has more energy, and as a result, the chances of...
pages: 7 (words: 1810)
comments: 0
added: 10/29/2011
Brief Synopsis: The book, To Know a Fly, is about a scientist and his lifelong fascination with science and the fly. Vincent Dethier is a biologist that loves science and sharing it with the world. The book explains how flies work, shows how science works, and shows a researcher genuinely enjoying his job. He goes into great detail describing his experiments, observations, and discoveries of flies. Dethier chose to study flies for many reasons such as: "the fly is always with us…there are about 50,000 kinds of flies sharing 'our' world," the fly has many amazing and interesting characteristics, and flies are free, easy to come by, and very cheap to use for experimental purposes, plus animals rights activists do not usually harass scientists for experimenting on flies. Of course, Dethier did mention at least one drawback of working with flies, which is that they have an "uncanny knack of escaping." Dethier says, "An experiment is a scientist's way of asking nature a question," and in this book, he asks nature numerous questions about flies through his different experiments, the first of which set out to discover why a fly walks about in its food and constantly sticks out its tongue. This observation led to speculation that flies taste with their feet. By "gluing" a fly to the end of a stick and dipping its feet into a sugar water mixture, one can observe that the fly has a natural reflex of flicking out its proboscis. Modified versions of this test also proved that flies can distinguish between different kinds of sugars, and that they reject salty, bitter, and sour tastes. Flies ignore artificially sweeteners, and are gluttonous over a rare sugar called fucose. Flies are similar to many people in the fact that they "prefer what tastes good to what is...
pages: 5 (words: 1184)
comments: 0
added: 12/27/2011
Initial problem When the river has an Suspendable Solids (SS) of 25mg/l and alkalinity of 13.5mg/l (expressed as CaCO3), 30mg/l of alum was added during the treatment process to make sure that the water passed water standards for the World Health Organisation WHO). But subsequently the amount of SS was found to have increased to 50mg/l. Logically, when this happens, by doubling the amount of alum added initially, we would be able to generate enough precipitate to filter off the 50mg/l of SS such that the amount of SS left in the solution would be able to pass WHO drinking water standards. This did not happen thus this report is to look into the probable reasons to why the move did not work and the possible solutions to the problem. Allowable Limits: According to the standards of Drinking water from World Health Organization (WHO), the acceptable range of alum dosage is from 5 – 50mg/l Thus, the 60mg/l of Alum added by the Plant manager has exceeded the acceptable limit. Analysis There may be various reasons to why the initial process did not work. Physical reasons (Note that we are adding in double the dosage thus the reactors/tanks might not be equipped or designed to take that kind of load) • The process of mixing alum might not be thorough enough thus the Al(OH)3 was not precipitated properly • Not enough time was allowed for precipitation to take place • The coagulant did not have enough time for it to be saturated with the SS before the coagulant was filtered off. • As the rate of chemical reaction decreases with decreasing temperature, assume that the temperature near the Hu river does not enhance the rate of reaction thus accounting for the decrease in precipitate formation Chemical reasons • There might not be enough alkalinity in the water thus the alum would not be able...
pages: 4 (words: 833)
comments: 0
added: 01/27/2012
The Bustle in a House By Emily Dickenson The Bustle in a House The Morning after Death Is solemnest of industries Enacted upon Earth - The Sweeping up the Heart And putting Love away We shall not want to use again Until Eternity. "The Bustle in a House", is focusing on the death leading to insight found in Emily Dickinson's poem. In another word the poem is about death of someone close and dear. The references to grief after the death of a loved one show that death is obviously a central theme. Also, it's about house cleaning which is being compared to coming terms with reality of death, by sweeping up the broken heart, and keeping the love of that person in memory, "And putting Love away". It is very obvious that the poem is about death from the first stanza indicates that the people move about the house to get their minds off the grief of the loss of a loved one. However, in line 6 the difference between cleaning and bringing oneself back together is that the person does not discard anything; they keep the memory with them. This is a brilliant way of Dickinson to use those to themes in a metaphor because of the fact that over coming grief of a deceased love one is somewhat similar to cleaning: people pick themselves up after being down. When closely, last two lines of the poem suggest how Dickinson feels about immortality. It seems that she believes that once we die that it will not end. Also, she feels that people should keep memories with them because once they go to heaven, or eternity, they will use them. In conclusion the theme in this poem is concerned with death. In My opinion that all the commotion that goes in a house when someone dies makes you forget about everything...
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added: 02/18/2012
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