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University Degree: Environmental Sciences
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How useful are the calculations of heritabilities in understanding human behaviour? Historically, the study of heritability (defined as the proportion of phenotypic variance that can be accounted for by genetic variance)
Twin studies are a classical method in heritability researches because they allow the investigator to compare pairs of individuals of the same age and family environment, but of different degrees of genetic relatedness, on some trait of interest. A greater resemblance for the identical twin pairs is taken as evidence that the trait in question is, to a certain extent, genetically determined. The study of adoptive families is another important design: it examines the resemblance of genetically unrelated individuals growing up together in the same family, as parents and children or as siblings.
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The result of this global warming is predicted to be an increase in precipitation, more dramatic weather conditions, and a rise in sea levels, with a rise of 4-8 inches already seen over the past century (EPA c.ref 6). El Nino has increased in frequency from once every 5-7 years, to once every 3-5 years (Showstack, 1988, c.ref 1). The ice caps are shrinking, with a 3,000km2 section of the Larsen B ice sheet in Antarctica disintegrating in just 35 days (National Snow and Ice Data Center, c.ref 4), which is indicative of the warming of the atmosphere, (Gelbispan, 1997, c.ref 1).
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Why is it difficult to achieve on the protection of the Global Environment? What concepts have been developed to overcome the difficulties?
Since 1960s, the Arctic ice pack has reduced its thickness by 40%. The sea level is rising 3 times faster over the past 100 years than the past 3 millenniums. The consequences of global warming are dangerous. For example, more extreme weather that cause floods, hurricanes, property destructions and diseases that threat human beings and animals2. Another important problem of the environment is ozone layer. There is a layer of ozone around the globe, at height between 10 kilometres and 35 kilometres, that protects human beings and animals from harmful radiation.
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DEFINE THE TERM HOMEOSTASIS AND USING EXAPMLES FROM A NAMED SPECIES, EXPLAIN HOW FEEDBACK MECHANISMS FUNCTION IN MAINTAINING HOMEOSTASIS
Definition and Principles The word Homeostasis comes from the Greek roots homeo and stasis meaning to remain the same. According to Tortora & Grabowski (1996) Homeostasis is a condition in which a body's internal environment remains within certain physiological limits. Homeostasis is frequently seeing as equilibrium. The internal equilibrium of the body involves the maintenance of a steady rate of concentration of substances and physical parameters such as water balance, blood concentration etc. Walter B. Cannon (1871-1945), an American physiologist, was the person that coined the term homeostasis in 1932 (Clancy, J, McVicar, A, 2002).
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Evaluate the arguments for and against the use of GM crops in developing countries. Which do you support and why?
Many people argue that genetically modified crops can be a good thing, particularly with regard to health. Genetically modified food has great potential as a relatively cheap source of human therapeutics, especially for the poorer countries. For example, 'In 1996 US researchers were genetically engineering a banana to produce an antigen found in the outer coat of the hepatitis B virus. If successful this banana could immunise children in developing countries for just a few cents per dose. Currently traditional hepatitis B vaccines cost between $100 and $200 per dose.'
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Wendy's vision is to be the quality leader in everything they do. REMOTE ENVIRONMENT Wendy's did show a lot of new ideas as far as the remote environment was concerned, for instance it established stored abroad, in the national expansion the franchisee agreement was for the area, a region and not for a store. Here she made agreements for time, area, technical associations and royalty. There are different problems that she has faced like inflation, energy problems, increasing labor cost and increasing beef price.
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With reference to a range of geomorphic hazards you have studied, examine the role of human activities in both preventing and controlling this hazard type.
The topic of mass movement is interesting, not least because it can occur on a very local scale, a scale that humans can prevent through a variety of means. The most primitive yet effective ways is to use harness the power of vegetation. Where the type of mass movement involved mainly soil, thus the hazard would be labelled a mudslide, vegetation and particularly trees can bind the soil together and prevent the slide. Tree and plant roots would not only bind the soil together, making it less susceptible to the power of gravity and the lubricating power of water, but they would intercept some of the water that would be present during a potential mudslide reducing the risk further.
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'What are: ozone depletion potentials (ODP) and how have they helped in understanding the current global situation on atmospheric ozone?'
has been formulated to help us gauge the effect of synthetic chemicals on depleting stratospheric ozone (Parker,1996). This work will discuss what ODPs are and what they have done to halt ozone depletion. ODP is a number gauged by a mathematical calculation (Appendix 1A) (Person,1997), given to a substance that refers to the amount of ozone destruction it can cause, over its entire lifetime relative to that of a 'referenced substance' which is CFC-11. So for example CFC-115 has an ODP of 0.6 (Appendix 2A) (EPA,2004), which destroys 3/5 as much ozone as CFC-11. ODP is often used in conjunction with Chlorine Loading Potential (CLP)
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O Clean Development Mechanism (CDM) => the governments and private sector companies of the industrialize countries can transfer clean technologies to developing countries. O Joint Cooperation => one industrialize country invests in other industrialize country to carry out a project to reduce the greenhouse gases emissions. ? Threats of the increase of the invisible gases, such as CO2. - Greenhouse gases: they catch a part of the solar energy. - Global warming: there is a 30% of CO2 in the atmosphere than when we started to burn en masse coal at the beginning of the Industrial Revolution.
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One of the attempts to combat the danger of increasing global warming was made at the Rio Earth Summit in 1992, where more than 160 countries (including the United States) ratified the UN Framework Convention on Climate Change (FCCC). The primary objective of the Convention was the " stabilization of greenhouse gas concentrations in the atmosphere at a level that would prevent dangerous anthropogenic interference with the climate system. "2 All Parties, that ratified the Convention, were committed to develop and publish a national database of the "anthropogenic emissions by sources and removals by sinks of all greenhouse gases" and
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This essay willdiscuss the role of the United Nations in assisting Small Island States adaptto climate change, making particular reference to Tuvalu and the 'environmentalrefugee' debate. 'Refugees', by definition are:
With residential population on Small Island States generally concentrated within coastal zones any rise in sea level will displace these populations (Davissen and Long, 2003, p6). Tuvalu, in particular, is extremely vulnerable to even small rises in sea level (Gillespie and Burns, 2000, p235; Ede, 2003, p40). Islands do not need to be covered in water for them to become uninhabitable. Once rising sea levels get into the food chain, the island would be unable to sustain habitation. In Tuvalu people are already being forced to grow root crops in metal buckets rather than in the ground due to the increased salinity of the soil (Davissen and Long, 2003, p5).
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In the United Kingdom human geography was not really explored in detail until after 1945. According to The American Heritage(r) Dictionary of the English Language, a study of a field of interest is a science if it observes, identifies, describes, investigates experimentally and theoretically explains phenomena, therefore both physical and human geography must be considered to be science due to the fact that both areas of geography can be studied methodologically. Despite the fact that the two aspects of geography are moving apart they are both considered to be sciences that have drawn on the idea of space.
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The damage caused to the environment in the past has been immense, and will take along time to recover, if ever. This progressive damage was checked early in the 1990's by a radical change in global rules and regulations governing the management and use of these chemicals; however, the danger still exists if not managed correctly. What are the properties of refrigerant gases?: In its liquid form it generally occupies about 40 times less volume than it does as a gas.
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The failure of the US and Australian Governments to ratify the Kyoto Protocol reflects the influence of short- term business considerations. Do you agree or disagree with this statement?
In 2001, President Bush unilaterally pulled the US out of the protocol (Bohringer & Loschel, 2003). The exit of the world's biggest economy, and a huge pollutant, was a devastating blow to Kyoto's aspirations and to the morale of the other signatories. After that, Australian is also out from the protocol although it is far smaller than the US, Australia's absence is nevertheless very important because of the proliferation of heavy industry. And both countries said that implementing Kyoto would damage the competitiveness of their industries.
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The Environmental Protection Agency (EPA), along with other groups and organizations, maintain that the responsibility for global warming and all of its consequences rests mostly on the shoulders of human beings. The EPA claims that the majority of the warming of the planet that has taken place over the last fifty years is attributable to human activities. Their argument is that "human activities have altered the chemical composition of the atmosphere through the buildup of greenhouse gases" (EPA website). This argument makes it difficult for humans to hide from its apparent responsibility in crippling this planet's state of equilibrium.
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Approaches to the past are largely determined by the intellectual climate of the times. To what extent does this statement apply to Book One of Herodotus?
At this time Athens was the centre of intellectual life and could boast an almost unique galaxy of talent. It was clear that Herodotus was impressed by Athens and this was demonstrated by his pro Athenian bias in his narrative. 'Herodotus was said to have recited a part of the 'Histories' at Athens and to have received a reward for it. To add greater precision, the absurdly high sum of ten talents was later fixed on the amount of the reward, the consequence of Athenian delight at being favourably depicted in the 'Histories'. This shows how he was influenced by the intellectual climate because he was eager to show Athens in a positive light and this was clearly because of him having lived there for a period of his life.
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How should the radioactive waste from nuclear power plants be disposed of? Why has the nuclear industry failed to find an acceptable solution to the problem of nuclear waster disposal?
The bundles are then submerged in water which acts as a coolant inside a pressure vessel. Left to its own devices, the uranium would eventually overheat and melt. To prevent this, control rods made of a material that absorbs neutrons are inserted into the bundle using a mechanism that can raise or lower the control rods. Raising and lowering the control rods allow operators to control the rate of the nuclear reaction. When an operator wants the uranium core to produce more heat, the rods are raised out of the uranium bundle.
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Temperatures are rising and the following observations prove this. Over the last century research has shown that average land surface has rose from 0.45 to 0.6 oC. This is due to the increase of these gases and some of these gases occur naturally in our atmosphere and some occur due to human activities. "The naturally occurring gasses include water vapor, carbon dioxide, methane, nitrous oxide, and ozone" (Hare, 204). Some human activities intensify the levels of most of these gases, which can lead to devastating impacts on the Earth.
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The term "marine pollution" was not widely used until 1967, when the tanker Torrey Canyon spilled more then 36 million gallons of crude oil just 20 miles off the coast of Cornwall, England. The United Nations Joint Group of experts on the Scientific Aspects of Marine Pollution (GESAMP) defined marine pollution in 1972 as "the introduction by man, directly or indirectly, of substances or energy to the marine environment (including estuaries) resulting in deleterious effects such as: harm to living resources: hazards to human health; hindrance of marine activities including fishing; impairing the quality use of seawater and reduction of amenities (Clark)".
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This is an example of shape and size constancy, the "ability to perceive objects as we know them to be despite changes in the sensory stimulation which they produce"1. The main focus of the top down theories is that perception allows our brains to go beyond the information given and fill in any gaps that may be missing with our own knowledge of the world. An example of how this process is used to 'decode' visual illusions uses the Ponzo illusion, as illustrated below.
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It is this communication, which ultimately leads to a change in the external environment. Right to the organ level or tissue organisation were for example the expulsion of urea changes the blood pH and osmolarity. These internal changes are countered by the excretion of hormones etc, (these substances share 4 main structural forms. Amines, steroids, prostaglandin and peptides) which start a "chain reaction" to nullify the change these hormones are either secreted via ducts (exocrine system) or directly into the blood stream, (endocrine system).
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Why do rivers flood? With reference to specific examples, discuss the effectiveness of measures that can be taken to prevent flooding.
They instead however affect the rate of discharge by controlling factors such as the shape of the channel (by introducing stone dykes), the bed-load (by dredging) and the flow rate of the river (by building dams) and by constructing lev�es. On the Mississippi a number of large engineering works have taken place in order to try and control the flooding of the floodplain. This was started because the shipping that navigated the Mississippi needed a minimum of 9 feet in order that they did not run aground.
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In environmental terms, water is the "life-support system" for the planet. Without a steady supply of clean, fresh water, all life would cease to exist. Although its great that we have an exceedingly large amount of fresh water in Canada, the perception we don't have to worry about it has led to misuse and abuse of the resource. Did you know... * In the City of Toronto, the average residential water use is about 248 litres per person per day? With every litre of water pumped weighing 1 kilogram, that's a tonne of water needed for a family of four each day.
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Although Diamond concedes that the "proximate cause" of European dominance was weaponry, disease, and technology, he argues that the "ultimate cause" is not because of racial superiority, but rather food production and ultimately environment. In Chapter 10: Spacious Skies and Tilted Axes he proves that a major factor contributing to the differing rates of the spread of crops is the orientation of the continents' axes: predominantly west-east for Eurasia, predominantly north-south for the Americas and Africa. Throughout the book, Diamond uses numerous rhetorical techniques, including posing initial questions and answering them using logical reasoning, presenting concrete scientific data, and conceding counterarguments.
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Impacts can be severe at all levels of economic development. However, flood impacts follow the pattern of other hazards, while LEDCs suffering the most deaths and MEDCs the highest total economic losses. River flooding results from a number of causes. By far the most common is excessive rainfall related to atmospheric processes, which include monsoon rains (these are long periods of heavy rain which normally occur once a year during its 'season') with intense mid latitude depressions, or a series of depressions bringing prolonged high rainfall, and tropical cyclones which bring high rainfall totals to the areas within their tracks.
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