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Year 10 Student Research Assignment – By Joel Jacob Aim: The aim of my experiment was to find out how an acid rain solution effects pine trees in different ways and whether limestone changes the effects of the acid rain. Introduction: My experiment will prove whether limestone neutralises the effect of acid rain on pine trees. Through this experiment we you would be able to safely neutralise acidic soil because of the testing I have carried out. Hypothesis: In my experiment I will conduct an experiment with the results showing that limestone neutralises the effect of acid rain on pine trees and will therefore keep the trees healthy. Method: 1. Line eight trees up in a line spacing them around 30cm apart. Space them this distance so it eliminates any possibility of trees and substances coming into contact with each other. 2. Label the trees in order from experimental variable 1, experimental variable 2, control 1, and control 2. 3. Add 14 grams of limestone to experimental 1. Put 28 grams of limestone to experimental 2, 21 grams for control 1 and NO limestone to control 2. 4. Make sure acid rain solution is watered down to strictly 10% sulfuric acid and 90% water. If this is not accurate it may burn the trees strait away or it could have an unnoticeable effect and ruin your experiment. Once you have the solution pour 120 ml of acid rain onto the leaves and around the base of all the trees except for control 1 which you put 120 ml's of town water on. You may wish to place onto a surface other than grass as the acid rain solution will most certainly kill the grass. 5. Record your results by taking photos and observing the changes that happen between the different trees. Once a week repeat the process of putting the limestone into...
pages: 4 (words: 1032)
comments: 0
added: 11/17/2011
Sitting in your room late at night, you listen to the gentle pitter-patter of the rain on your window. It is so soothing and relaxing. Have you ever wondered what the rain is really made of? Is that simply water or is it acid slowly streaming down out there? That rain you hear might be acid rain, which is caused by sulfur-dioxide emissions and shown to be harmful to plants, animals, humans, and even buildings and structures. The commonly used terms "acid rain" and "acid precipitation" describe specific forms of a type of pollution described generally as "acid deposition." Harmful gases that rise into the air mix with cloud moisture, sunlight, and oxidants. There they chemically combine into dilute sulfuric and nitric acids, which fall back to the earth. This is acid deposition. The major contributing pollutants are sulfur dioxide and nitrogen oxide (Morgan, 5). "Acid rain" is basically rainwater with a pH level lower than 5.6 (Morgan, 3). The term pH means "potential hydrogen". When a substance has a pH level of 7, it is completely neutral with the same number of hydroxyl and hydrogen ions (Pringle, 6). Acidity in the atmosphere can be changed by many natural things. When a volcano erupts, sulfur dioxide is spewed out. Droughts produce unusually dry soil conditions allowing dust particles to be carried upward into the air, neutralizing the acids that may be present at the time (Pringle, 4). Acid rain can come in concentrations sometimes more acidic than lemon juice. These pollutants reach the earth in rain, snow, hail, sleet, or fog. The rain at the beginning of a shower is usually more acidic than the rain that follows. Dry acidic particles can also fall from the atmosphere. Because wind can carry gases and moisture for hundreds of miles, even areas far away...
pages: 7 (words: 1819)
comments: 0
added: 10/23/2011
How does temperature affect the rate of reaction between Hydrochloric acid and marble chips? Aim From this investigation, we intend to find out if the temperature of acid, in this case Hydrochloric acid, affects the rate of reaction between itself and marble chips. Hypothesis We expect to find that the higher the temperature of acid, the quicker the rate of reaction. The rate of reaction will depend on the rate of collisions between particles, we expect the rate of collisions to be greater the higher the temperature of acid. Our hypothesis is based on and supported by the scientific theory that : " Reactions can only occur when particles collide with enough energy. Increasing the temperature of the reactants increases the speed of the reactant particles. The particles collide more often and with higher energy, resulting in an increase in the number of fruitful collisions." Extract taken from BBC GCSE Bitesize chemistry book. If this scientific theory is correct, then it should give us a clear explanation for the results that we gain from our experiments. List of apparatus · 0.4M Hydrochloric acid · 25 cm3 measuring cylinder · 250 ml beaker · 100ml conical flask · Bung · Delivery tube · Gas Syringe · Water baths at temperatures 40º, 60° and 80°C...
pages: 1 (words: 213)
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added: 02/21/2012
The African Wild Dog, known scientifically as "Lycaon Pictus", can be found in savannas, open woodlands and grasslands in its native homeland, Africa. More specifically, they are usually found in Botswana, Zambia, Tanzania, South Africa, Zimbabwe, Senegal, Namibia, and possibly Kenya. African Wild Dogs are the size of medium domestic dogs. Their average weight is between 35 and 80 pounds and ranges from around 30 to 45 inches tall, and it's average lifespan is between 8-10 years. The African Wild Dog Latin name, as mentioned above, is Lycaon pictus, which means "painted wolf-like animal". Their coats vary from shades of brown, black and beige, which are thick but short and hard to maintain. The wild dog has unique shearing teeth, large hyena-like rounded ears and dark brown skin around their eyes. They also are very different from wolves and other domestic and wild dogs in that they have four toes on their front teeth, unlike the others, who have five toes, which is the main difference between Lycaon and Canis, as explained below. They are long legged, thin and slender, with a broad skull and a long and thin snout. They are also known as the Cape hunting dog, and is the single species in its gene group. They belong to the family Canidae, the dog family, and is a distant cousin of the domestic dog, known as Canis familiaris and its predecessor, the wolf, whose scientific name is Canis lupus. Wild Dogs usually live in packs of 10, however packs as large as 40-50 have been sighted. These packs cooperate for the hunting for the pack and raising pups. The pack does not stay in the same area constantly, it moves over an area of several hundred square kilometres. Scientists have found that they can run at 55-60 kilometres and hour for around...
pages: 3 (words: 674)
comments: 0
added: 02/10/2012
Anger is a basic emotion (Oatley, 1992) that can be defined as a negative feeling state associated with specific cognitive appraisals, physiological changes and action tendencies ( Kassinove & Sukhodolsky, 1995). It has been distinguished from related concepts of hostility and aggression ( Friedman and Spielberger) and a substantial body of literature has been accumulated which necessitates a distinction between anger and anger rumination. Conceptualization of the anger rumination was influenced by the social-constructivist ( Averill, 1983) and factor-analytical ( Spielberger, 1988) models of anger. Anger rumination is considered as a relatively independent component within the sequence of broader anger phenomenology. Generally, if anger is viewed as an emotion, anger rumination can be defined as thinking about this emotion. The Anger Rumination Scale (ARS) was developed to assess cognitive processes that unfold after the emotion of anger has been triggered or generated. Deffenbacher (1999) explicated the difference between internal and external triggers of anger. External anger eliciting events include identifiable circumstances such as being cut off in traffic. Internal events that may trigger anger include thoughts and memories of prior anger-provoking events such as thinking about an ex-spouse. Anger experiences are further shaped by cognitive appraisals, specifically those of unfairness, blameworthiness, and intentionality ( Kassinove & Sukhodolsky, 1995). Spielberger (1988) labeled the phenomenology of anger experience as state-anger, which was defined as a transient psychobiological feeling that varies in intensity from mild irritation to fury and involves the concomitant activation of the autonomic nervous system. Correspondingly, an individual's tendency to experience state-anger with higher frequency and in response to a wider range of situations is referred to as trait-anger. We propose that anger generation and anger experience processes are intertwined with anger ruminative processes, which can be responsible for sustaining and augmenting anger. This paper is concerned with anger rumination, unintentional and...
pages: 7 (words: 1677)
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added: 01/19/2012
Caleb Pan Report # 1 Problem The problem of the experiment is how a diet in a pregnant mother can change genes in her offspring. Scientists used a fat yellow mouse that carried a gene made the color of their coat different and leads to obesity, diabetes, and cancer in the mouse. If scientists can figure out this strange occurrence, they are able to help human beings in perfecting their diets and may even lead to better drugs to minimize the risk of cancer and obesity. Observations During methylation, a process in which biological mechanisms other than mutations that affect how a gene or genes function, a methyl group attaches to a gene. This process stops genes that are not needed by a cell. The genes on one of the two X chromosomes in each female cell are silenced by this process, which are not needed. Another observation of methyl groups and other small molecules help relax the coils of DNA so that inactive genes are active and vice versa. The tight coiled DNA may inactivate genes, so, methylation helps relaxes it and, therefore, genes that were inactivated become active once again. Scientific Law The methyl groups that creates the process of methylation, come from the foods we eat. They are a non-permanent way of "tweaking" the genes in a non-permanent way(mutation). In this instance, the yellow mouse was fed with vitamin supplements until it gave birth to a normal mouse. A scientist chose a strand of DNA that happens to have transposon. This strand conatains the past of viral infections. This acts as an on and off switch for genes. The methyl groups attach to the strand, and shut off the whole gene to prevent infections. Hypothesis Scientists wonder if more methyl groups are introduced in the a mice's diet can affect the infected gene to a greater...
pages: 3 (words: 588)
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added: 08/07/2011
Economic Analysis of Hawaii Hawaii, with an area of 28,313 sq. km (10,932 sq. mi.), is the 43rd largest state in the U.S.; 6.9% of the land is owned by the federal government. It consists mainly of the Hawaiian Islands, eight main islands and 124 islets, reefs, and shoals. The major islands in order of size are Hawaii, Maui, Oahu, Kauai, Molokai, Lanai, Nihau, and Kahoolawe. Population growth has increased by 80,000 persons over the past five years. Demographics show a large number of Hispanic origin: Asian Hispanics are the most populated with white Hispanic and Asian non-Hispanic following. Hawaii's economy has been long dominated by plantation agriculture and military spending. As agriculture has declined in importance, the economy has diversified to encompass a large tourist business and a growing manufacturing industry. Hawaii's economy has changed drastically since statehood. In 1958, defense, sugar, and pineapple were the primary economic activities, accounting for 40% of Gross State Product (GSP). In contrast, visitor-related expenditures stood at just over 4% of Hawaii's GSP prior to statehood. Today the positions are reversed; sugar and pineapple constitute about 1% of GSP, defense accounts for just under 11%, while visitor-related spending comes close to 24% of Hawaii's GSP. The movement toward a service- and trade-based economy becomes even more apparent when considering the distribution of Hawaii's jobs across sectors. The share of the economy's jobs accounted for by manufacturing and agriculture have declined steadily since 1959 and each currently makes up less than 4% of total jobs in the economy. At the same time, the shares of jobs in wholesale and retail trade and in services have risen, standing at about 23% and 28%, respectively. Since 1991, Hawaii's economy has suffered from rising rates of unemployment . This stands in marked contrast to the period 1980 to 1993, when the...
pages: 5 (words: 1279)
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added: 11/11/2011
Scientific Process of Identification Observation: Why do the nations of Eastern and Southern Africa have the world's highest rates for sexually transmitted diseases amongst the population? How does the local government play a role (if any), in the preventative measures that are taken by its citizens? What is the correlation between social and economic conditions and STD's in these nations? Hypothesis: I believe that the economic and social conditions of the nations of Eastern and Southern Africa are the largest influences on the amount of sexually transmitted diseases that occur. If African nations of the Eastern and Southern regions governments had stability, I believe that rate of AIDS transmission would greatly decrease. However, due to the lack of proper funding, due to corrupt governments transitioning to democracy, the education in these nations on sexually transmitted diseases is very small. The governments of these nations don't take any preventative measures to ensure that STD's epidemic isn't further dispersed. There is no education about STD's in these countries because the economies are dependant on children to make money. So children can't learn about how to prevent STD's from spreading. Experiment: Poverty, oppression, and urban migration have been the factors listed by the regional governments as the leading factors in AIDS transmission. However, they go deeper into saying that, "These colonial legacies have looted and reduced the continent to a state of poverty, conflict, chaos, criminality and disease. Many African nations have ceased to exist; law and order have all but disintegrated, plunging countries into bottomless pits of inter-ethnic genocide, wars, mayhem and murder; while natural disasters, death and ruin are unprecedented." ( The major factor that plays a role in African society is that HIV/AIDS ruins the economic engine room of African societies for professions like; teachers, professors, doctors, nurses, engineers, lawyers, community leaders, and so on. The...
pages: 3 (words: 731)
comments: 0
added: 12/06/2011
HIV vaccine is possible. When HIV was identified as the cause of AIDS in 1984, researchers famously predicted that a preventive vaccine was right around the corner. Of course, it turned out that the task was not so easy, as in the early days of the epidemic, very little was understood about the virus. Yet in the time since, we have learned much more. In fact, we know now more about HIV/AIDS than other diseases against which vaccines have been developed. Researchers are taking clues from the ways the body naturally responds, or fails to respond, to HIV. For example, on average 10 years elapse from the time one is infected with HIV to when the virus has done enough damage to warrant AIDS diagnosis. This means that the immune system has some ability to control HIV, albeit temporarily, and the role of a vaccine will be to boost these defenses to where they can deliver a decisive blow. Additionally, there are rare individuals who exhibit an exceptional ability to tame the virus, and analysis of what is different about their immune systems is yielding ideas for vaccines. For example, some female sex workers have remained HIV uninfected for years, despite repeated sex without condoms. Researchers are building and testing vaccines designed to stimulate killer and other immune cells that are believed to be responsible for these women's upper hand against the virus. Already experimental vaccines against HIV, a close cousin of HIV that infects monkeys, have been shown to prevent AIDS. What works in animals does not always translate into humans; still this is an exciting proof of concept. Why makes the development of a new vaccine so difficult Creation of new vaccine is never easy, the development of a vaccine to prevent HIV infection, or even, for that matter, to delay or temper the...
pages: 5 (words: 1151)
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added: 01/11/2012
Donna Kundu In some parts of the world there are still wars being fought and dictators in power. There are societies which consider themselves at the peak of evolution and progress. They are able to create state of the art automobiles, luxurious homes, efficient and organized industries, complex computerized machinery and atomic weapons. Many societies are governed by a democratic system which herald a belief in freedom. All societies, regardless of their political and economic makeup, are also ruled by a special class of dictators; these dictators are unseen to the naked eye, and are invincible. These invisible tyrants are microorganisms. Underdeveloped countries, technologically advanced countries, and those in between are at the mercy of these microorganisms, which come in many forms - viruses, bacteria, fungi and parasites. The most dangerous of these forms is the virus. Some viruses, such as the common flu, are considered to have a fairly detrimental capacity. The flu can incapacitate a human for several weeks with various symptoms such as bodily soreness, fever, bronchial complications, and even pneumonia. But while these conditions can be painful and frightening, we are usually confident that proper medication and rest will take care of the matter. However there is a much more severe and indiscriminate tyrant, with enormous corrupting influence, capable of infiltrating all of civilization. Scientifically, it is a submicroscopic pathogen consisting of a particle of nucleic acid, enclosed in proteins, and able to replicate only within a living cell. Socially, it is responsible for an enormous amount of chaos and fear in the world today, and pronounces the human fault of ignorance. Can it be considered to be a modern plague? This complex and confusing king of all tyrants is called Human Immunodeficiency Virus, or HIV. HIV is a retrovirus. Retroviruses are commonly identified in many animal species, but HIV...
pages: 4 (words: 937)
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added: 10/04/2011
Hypothesis Larger animals lose heat at a lower rate than smaller animals. As the organism gets bigger the volume and surface area ratio decreases. This means that there is less surface area to lose heat from. If we use penguins as an example, the larger penguins live closer to the poles that the smaller penguins. So smaller animals have a higher surface area to volume ration and larger animals are the opposite. As the size of the animal increases the rate f heat loss decreases. The rate of heat loss depends on the surface area to volume ratio. The total heat production of 'warm – blooded' animals- depends upon the volume of metabolically active tissues whilst the rate of heat loss depends upon the surface area. For this reason, animals living in colder climates tend to be large whilst living in a hot climate they are generally smaller. This is known as Bergmann's rule and is observed in many species. The metabolic rate per gram of the smallest mammals is approximately 100 times faster than the largest. They have a large appetite enabling them to maintain a high metabolic rate. Heat gain and loss depend on the ratio of the surface area to the volume (the Surface Area/Volume ratio) because heat is stored in the volume of an animal but gained or lost over the surface. The higher the Surface Area/Volume, the faster an animal can heat or cool. Since as animals get larger, the Surface Area/Volume gets smaller (Volume increases faster than Surface Area as animals get larger), large animals heat or cool more slowly than do small animals. Length ofOne side Total surfaceArea Volume Ratio of surface area to volume 1 6 1 6:1 2 24 8 24:8 = 3:1 3 54 27 54:27 = 2:1 4 96 64 96:64 = 3:2 = 1.5:1 5 125 125 150:125...
pages: 4 (words: 1008)
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added: 01/24/2012
Then the sky turned red, toxins over head, everybodies dead, everybodies dead. (GutterMouth; Nitro Records; 1995) In 1948, the industrial town of Donora, Pennsylvania suffered 28 deaths because of the thick smog. Air pollution is an ecological problem having to do with toxins in the air. There are a few things the human race has done to try to prevent air pollution from taking such a serious toll. Two of these are the Clean Air Acts and the increased use of solar power over coal power. By creating electric cars, the pollution caused by gasoline powered cars will be lessened. If the pollution is not stopped, it will cause life on earth as we know it to cease. Air pollution causes a number of health and ecological problems. It causes health problems like cancer, emphysema, and asthma. It also causes the depletion of the ozone layer which results in global warming and melting of the ice caps. Up until the industrial era, the air was fairly clean. The use of smokestacks and the burning of fuels put many pollutants in the air during this period of time. The increased use of fossil fuels today also builds on this. There have been many attempts at stopping air pollution. The Clean Air Acts were effective for a little while. They made using some polluting substances illegal. This did not work because people simply did not listen. Solar Energy is another attempted solution. This type of energy is good because it is an alternative energy source to coal and other polluting fossil fuels. The problem with solar energy is that it is extremely expensive, but it has been used extensively throughout the world. One of the more effective ways of eliminating air pollution is the making of electric cars. The use of these electric cars would completely reduce the amount of pollution in the air caused by gasoline powered cars. These cars are run on batteries instead of gasoline...
pages: 2 (words: 516)
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added: 12/01/2011
TOPIC RESEARCH Lead is one of the most harmful, but yet most unexpected air pollutants in the world today. For many years Lead has been known as a poisonous substance, nevertheless still to be ignored by some. Lead does a large amount of damage to the human body. And the bad thing about it is that if I had to name some of the most harmful air pollutants in the world I probably wouldn't have even mentioned lead. Lead is very harmful to the human body. High levels of exposure to Lead can damage the blood, brain, nerves, kidneys, reproductive organs, and even the immune system. While on the other hand lower levels which are more commonly associated with current exposures can result into impaired mental functioning and development in children and raising blood pressure in middle-aged men. What makes lead even more dangerous is that it accumulates in the body so bad that even small doses can be harmful to the body. Some of the remaining sources of lead pollutant includes lead smelters, incineration of lead batteries, and burning lead-contaminated waste oil. However, the most common sources of current lead exposure are indoors from old lead-containing paint and soil. Many actions are being taken in effort of reducing lead air pollutants, but there still can be even more things done to help reduce this problem that is affecting the people in the world that we live in. And it all starts with everyone looking at themselves first. One plus is that due to major reductions and now the elimination of lead in the world's gasoline, there has been a significant decrease in public exposure to lead in outdoor air....
pages: 2 (words: 280)
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added: 01/11/2012
Air Pollution has crept into every aspect of our lives and has grown at alarming rate. From garbage, factories, vehicles and others that can destroy many precious lives. we don't have to look far to find the culprits because we humans are the ones polluting our world. There are many reasons why children get sick. At home, the garbage we improperly dispose off emits a foul smell and contributes a fair share of air pollutants. On our streets, thousands of smoke belching vehicles continuously discharge a large percentage of air pollutants. Around urban areas and in countryside, factories, powerplants and manufacturing plants emit large columns of dark smoke containing elements that poisons the air. These things are very harmful and death threatening. If we continue doing these, there will be no world for us to live in. Unless we are vigilant about our environment, we will soon find ourselves suffocating for lack of clean, fresh air. What can we do as individuals to protect ourselves? One way is to put our garbage in covered trash receptacles. Another is to minimize our waste by segregating and recycling. Still another is to plant trees for a sure supply of oxygen. Trees take in the carbon dioxide that poisons usa. They give off oxygen that we need for breathing. ------------------------------ We must learn how to preserve our environment to make everybody happy and healthy. With a little help from us, we can save our own selves. We should thank God for giving us a beautiful and clean environment. Lead is one of the most harmful, but yet most unexpected air pollutants in the world today. For many years Lead has been known as a poisonous substance, nevertheless still to be ignored by some. Lead does a large amount of damage to the human body. And the bad thing...
pages: 10 (words: 2564)
comments: 0
added: 09/23/2011
Pollution is one of the most worrying problems of our time. This problem surfaced during the industrial revolution. The great industrial revolution brought about many positive changes to the world; better transportation, cheaper products, and a better life. However, with it's riches came the price, pollution. At the beginning of the industrial revolution, no one paid any attention to the problem of pollution. As the science, progressed people started to realize this problem. Air pollution arises from many sources. The burning of gasoline in automobiles produces harmful gases and incineration of products. From various factories come millions of particles that are carried off in the air. Chemical plants produce gaseous by-products that are toxic when their concentration is high enough. As parts of the world become more industrialized, air pollution has generally increased and new health hazards have developed. Air pollution can result from causes that we can not control. For example, forest fires, dust storms, and volcanoes. Acid rain is one of the products of air pollution. Acid rain is created when raindrops combine with the polluted air. Acid rain causes erosion of buildings, destruction of crops, and other assets. Air pollution also causes global warming. . According to some predictions, significant alterations in climate patterns could become apparent in a few years. Estimates of global average temperatures have projected an increase of as much as 9o F before the year 2100. There are two kinds of sources of air pollution indoor and outdoor air pollution. The indoor air polluters include many products, from cleansers to furnishings, which release harmful organic compounds into the air you breathe. The EPA has measured levels of organic compounds in both rural and suburban homes that range from two to five times the levels of outside air. Another indoor pollutant is called mold, a microscopic organism,...
pages: 6 (words: 1509)
comments: 0
added: 11/06/2011
Air pollution is a serious problem in the economy. Even though it has gotten much better, it still needs a lot of work. In the last four years, thousands of people have become ill and died from unusually heavy levels of air pollution. Each year the US dumps about 130 million metric tons of pollution into the air. That amount is more than half a metric per every person in the country and one million metric tons in the atmosphere for every person on earth. The major component of smog and ozone can cause serious respiratory problems, such as breathing difficulty, asthma, and reduced resistance to infection. Carbon monoxide when inhaled replaces oxygen in the bloodstream and can impair vision, alertness, and other mental and physical capacities. Global warming increases the chances of skin cancer and other adverse effects. Toxic chemicals emitted into the air by human activities may have serious short and long term effects on human health and environment. Our cars emit many toxic substances including large amounts of carbon monoxide which interfere with the bloods ability to absorb oxygen. This, in turn, may threaten the growth and mental development of a newborn baby. Over half of our air pollution is caused by automobiles. Exposure to airborne toxins in the workplace is generally much higher than in the ambient. Harmful indoor pollutants include airborne pathogens, such as viruses, bacteria, and fungi, as well as radioactive gases. In the upper atmosphere, where ozone is needed to protect people from ultraviolet radiation, the ozone is being destroyed by manmade chemicals such as chlorofluorocarbons. Health related standards for one or more of the criteria pollutants are not being met. The earth radiates the heat as infrared rays, some heat escapes, but carbon dioxide and other gases in the atmosphere trap the rest, warming...
pages: 2 (words: 407)
comments: 0
added: 11/10/2011
Without biological diversity our planet will have a hard time supporting the growing human race, and yet by acting quickly and wisely we can stem this loss of diversity. The first step we must take in continuing the development of biodiversity is to gain understanding of it. What is biodiversity? On its basic level, biodiversity is the grand assortment of the many and varied forms of life and their habitats. There is diversity at the minute level that is represented by each species gene-pool. A glance around in a public shopping center will quickly reveal many variations in the human gene-pool. We can also find diversity shown by the different species of living organisms and plants on earth. To date scientists have identified 1.75 million species: however, estimates for the total range from three to one hundred million with an average consensus of fourteen million. On the larger scale, diversity is found with the many ecosystems of the planet; such as: deserts, coral reefs, rain forests, swamps, and oceans to name a few. As we the human race have evolved as an integral part of our planet, we must wonder how we will fare without the diversity nature originally provided. The importance of biodiversity can be seen readily in some of the services and goods ecosystems provide. For example, swamps and wetlands give us essential water purification. These ecosystems make use of their various plants, animals, and micro-organisms to act as sponges. These "sponges" filter sediments and toxins from inflowing waters. Another example of this importance is pollination. By the actions of animals and insects our commercially grown crops are pollinated. Farming is worth six to twelve billion a year to our country. A little known fact is that many of the ecosystems contain the natural enemies of many disease carrying...
pages: 3 (words: 774)
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added: 11/03/2011
Reflex Arcs and Reaction Rate Objective: To investigate different reflex arcs and reaction rate. Materials: rubber reflex hammer penlight or microscope light 30 cm ruler table or chairs Procedure: KNEE JERK 1. have subject sit on a chair with their legs crossed and relaxed 2. using a reflex hammer, locate and gently strike the tendon below the knee cap. 3. a) describe the movement of the leg 4. ask the subject to clench a book with both hands and strike the tendon again. b) compare the movement to 3a ACHILLES REFLEX 5. have the subject remove their shoe and kneel on a chair with their feet hanging off the edge of the chair. Push the toes towards the leg of the chair and lightly tap the Achilles tendon with the reflex hammer. c) describe the movement of the foot BABINSKI REFLEX 6. have the subject remove a shoe and sock, sit on a chair and place the barefoot on an adjacent chair for support. Quickly slide the reflex hammer across the sole of the foot from heel to toe. d) describe the movement of the toes PUPILLARY REFLEX 7. have the subject close one eye for about one minute. When the open the closed eye, compare the size of the pupils. e) which pupil is larger? 8. Ask the subject to close both eyes for one minute. Once the eyes are opened, shine a penlight in one of the eyes. f) Describe the changes you observe in the pupil. REACTION RATE 9. Ask your subject to place his or her forearm flat on the surface of a desk with their entire hand extended over the edge. 10. Ask the subject to place the index finger and thumb approximately 2 cm apart. Place a 30 cm ruler between the thumb and forefinger of the subject. 11. Indicate when ready, and release the ruler. Measure the distance the ruler falls before being caught. Repeat the procedure for...
pages: 2 (words: 509)
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added: 01/04/2012
Fossil Fuel is an essential energy source for living. Fossil fuels supplies us with energy for our homes, it runs our technologies and powers our engines for business, recreational or personal use. Fossil fuel is mainly oil and coal, it is found in the grounds which take millions of years for nature to produce. However, through the slow production of such energy source and the ever increasing rate of the use of the fuel, it would eventually run out within time. Therefore we seek for an alternative which is still rich in content and can carry the same duties in supplying us with our energy needs. Nuclear power is believed to be the best alternative to fossil fuels because they both use the same key in producing energy, the ability to cause steam. Therefore extensive research has been put into nuclear power. The desired outcome of this research is to use nuclear power to produce efficient energy to run homes, offices and engines. To do this involves a process using uranium to produce heat, which causes steam to run its generators. The uranium is collected in bundles of rods, submerged in water to activate the uranium. The heat is cooled with water, this is where the steam comes from and the steam spins the turbines, which drives the generators. This is an effective way in producing energy and large amounts of it. However there is not yet a way of using the nuclear power process or uranium to run engines. This means further research needs to be made to find a way in replacing fossil fuels in the engines department. Nuclear energy is strong and reliable, only a small part of uranium is needed for a large amount of energy. Therefore the use of nuclear power can assure us with a very...
pages: 2 (words: 448)
comments: 0
added: 02/03/2012
Most people take many things around them for granted. They get up in the morning, turn on the light, open their can of peaches then eat the peaches with a spoon. The light goes on magically, the peaches are still fresh in their can to no surprise and it takes little to no effort to lift the light spoon to the mouth. All these things happen or are there thanks to Aluminium. Amazingly enough, aluminium does not magically appear and to be produced lots of raw materials, chemical reactions, money and time are needed. The process in which aluminium is made involves three complex steps; the mining of bauxite, the refining of aluminia and the smeltering of aluminium. The first step, mining Bauxite, is planned five years in advance so the areas that are to be mined can be developed. Once mined the Bauxite has to be processed before being shipped to the refineries. In a beneficication plant, fine particles are removed from the Bauxite by screening and washing it. It is then placed on stockpiles before being shipped away. In the second step aluminium oxide, which is Alumina, is removed from the Bauxite using the Bayer Refining Process. Firstly the bauxite is ground up into fine particles and is mixed with hot, caustic soda (NaOH) solution to dissolve the alumina and some forms of silica. Not dissolved in this process are other elements such as silica, iron and titanium. These are then filtered off. The alumina and caustic soda solution is then put into rows of thickener tanks. In the tanks a fine red mud sinks to the bottom as well as the silica, iron and titanium. Remaining alumina trihydrate is then filtered to clean it even more. The solution is then cooled, concentrated and stirred in open top tanks until pure alumina...
pages: 6 (words: 1596)
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added: 10/15/2011
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