Explain how twin and adoption studies attempt to distinguish genetic and environmental factors underlying the onset of schizophrenia within families. Review the studies and discuss two limitations of this.

Psychology Essay Explain how twin and adoption studies attempt to distinguish genetic and environmental factors underlying the onset of schizophrenia within families. Review the studies and discuss two limitations of this. Schizophrenia is the label applied to a group of disorders characterised by severe personality disorganisation, distortion of reality, and an inability to function in daily life. Symptoms are mainly disturbances of thought processes, but also extend to disturbances of emotion and behaviour. There are two symptom categories - acute schizophrenia characterised by positive symptoms, such as hallucinations and delusions; and chronic schizophrenia, characterised by negative symptoms such as apathy and withdrawal. However, DSM-IV has now moved away from these definitions and classified schizophrenia into three main sub-types: paranoid, disorganised and catatonic. Understanding Schizophrenia More research has, probably, been devoted to trying to understand the nature of schizophrenia than any other mental disorder. Somatogenic approaches have focused on the role of genetic mechanisms influencing the propensity to develop schizophrenia, while psychogenic approaches emphasise the effect of adverse childhood experiences, particularly abnormalities in family interaction in the aetiology of the disorder. Twin studies Twin studies offer a

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  • Level: AS and A Level
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Agricultural Issues: Genetic Modification.

Agricultural Issues: Genetic Modification Scientists are developing ways to make new genetically modified (GM) food that could transform the way we feed ourselves. GM crops may enable more food to be produced from less land using less water and fewer chemicals. However, some people question whether this "gene revolution" will really reduce hunger in the world. Others worry that it is being pushed too quickly without enough consideration of its long term impact. Throughout the world there are drastic inequalities in food supply with the emergence of areas of surplus and famine. The cause of such inequalities vary from physical to human and political. Most of the responses to these problems have been driven by high income, high technology MEDC's or trans-national companies. The impacts of the Green Revolution, intensification of farming and the development of genetically-modified foods have varied. Some are economic while others have been social or environmental: some have brought benefits, while others have created problems and some may be focused upon the environment e.g., organic farming. Throughout the world genetic modification has been used freely for more that a decade as a research tool for medical purposes and in food ingredients. It holds exiting promise, not only for conquering disease, eliminating pests and contributing to the knowledge economy but for enhancing

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Advertising my local area

Venez Visitez Londres! J'habite ( Kingsbury. Il y a un beau parc, des magasins et des banques. Il y a aussi une gare et une (glise, mais il n'ya pas de piscines. Il y a aussi beaucoup d'(coles un grand lyc(e et plusieurs (coles primaires. Il y a une tr(s grande colline et bien s(r beaucoup de circulation surtout le matin et le soir. ( part de (a c'est une ville assez calme et tranquille. J'aime bien mon quartier et je peux jouer au foot dans le parc avec mes amis. Il y a beaucoup de restaurants, o( on peut manger de la nourriture des pays diff(rents. Pr(s d'ici nous avons un centre sportif, o( je peux jouer au badminton. C'est ouvert tous les jours et j'y vais souvent avec mes amis. Il y a pas mal de cin(mas pr(s de Kingsbury. La vie est assez anim(e. Et il y a un grand nombre de distractions. Par contre si vous aimez la campagne il est tr(s facile d'y aller en voiture ou ( bicyclette. L'avantage de vivre ( Kingsbury c'est qu'on peut facilement visiter le stade de Wembley. Evidemment si vous aimez le football c'est formidable d'y aller. Moi, j'aime le club d'Arsenal et je voudrais voir cette (quipe un jour. Je me demande si on va avoir du sport au stade pendant les jeux olympiques de 2012. Il faut aussi dire que Kingsbury se trouve pr(s du centre de Londres et si je prends le train je peux y aller en quelques minutes pour visiter le mus(e de Madame Tussaudes et d'autres

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  • Subject: Modern Foreign Languages
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Compare how the poems What Were They Like and Vultures present the cruelty of war.

Compare how the poems "What Were They Like" and "Vultures" present the cruelty of war. Both poems, "What Were They Like" (WWTL) and "Vultures" has conflict as a common theme. "WWTL" is about the Vietnam war and the lasting effect of war on the culture, whereas "Vultures" is loosely about WWII and the conflict between good and evil. One of the ways that Levertov presents the cruelty of war in "WWTL" is through the ignorance of those in conflict. The structure of the poem takes the form of question and answer, which could perhaps be seen as a soldier asking a person of a higher status, because of the use of 'sir'. By asking about the past, the soldier is ignorant of the effect that he has on the 'people of Viet Nam'. In the same way the 'Daddy' in "Vultures" ignores the 'fumes of human roast'; but action cannot be without consequence, which causes the experience 'clinging rebelliously'. Here both poets imply that not knowing the consequences of war is the cruellest act of all, otherwise lives and culture would not be lost. In "Vultures", the cruelty of war is also shown through the conflict of good and evil. Achebe contrasts the beauty of 'love' to the ugliness of vultures; this shows that those at conflict can unite even with their differences. He admires the 'pebble on a stem' as well designed, similar to that of a tank, but at the same time well designed machines could

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effects of substrate concentration on the activity of the enzyme catalase.

Investigate the effects of substrate concentration on the activity of the enzyme catalase. To explain this, catalase is an enzyme found in potato cells, catalase breaks down the substrate Hydrogen-Peroxide into water + oxygen. Hydrogen Peroxide itself is a waste product found in potatoes and other fruit + vegetables. When I do this I will see with different concentrations of the substrate and see how quick the enzyme catalase works on it. The four things that affect the rate at which the substrate and enzyme would react are as follow:- * Susceptibility of temperature change. * Susceptibility to PH changes. * Enzyme concentration. * Substrate concentration. Now I will explain each one of these in detail and how they can change the rate of reaction in many different ways. Susceptibility of temperature: - Chemical reactions can be speeded up by heating the reactants, this makes molecules speed up and have sufficient energy for more successful collisions. If the temperature is too high the enzyme would vibrate and it would denature because the active-site would change shape. Susceptibility of PH changes: - Enzymes can be denatured by changes in PH. This happens because the ionisation of the Amino acids changes, the Ionic bonds with stabilise the enzyme, that shape is broken so they are no longer stable. So you need the right PH for the ionic bonds to stay stable for the

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The overall finish of my Family Fruit cake was excellent. It was golden and crispy brown at the top in relation to appearance. It gave off a wonderful aroma of freshly baked sponge cake when it was being baked.

The overall finish of my Family Fruit cake was excellent. It was golden and crispy brown at the top in relation to appearance. It gave off a wonderful aroma of freshly baked sponge cake when it was being baked. It looked mouth watering once it had cooled down. The flavour of the cake was fruity and the texture was spongy and moist. It looked colourful also because of the different colours of the dried fruit I had added. I was amazed with the overall finish of the cake because it was neat and it was brilliant in taste, texture and appearance. I couldn't find any bad points for the overall finish of my cake. I had sprinkled the top of the cake with some dimera sugar (brown sugar) which gave it a crispy top. The sponge was light yellow or pale in colour. The sponge was well risen because the size of the cake was fairly thick. The appearance was golden brown with a crispy touch which made my cake more appealing. It was light, crumbly and soft in texture and the flavour of my sponge was sweet and it wasn't eggy. Those were all the good points of the cake but the bad point was that when I spooned the mixture into the baking tray, it had some dry flour in the middle which wasn't mixed in with the rest because of the mixture being too thick with all the fruits. The sponge didn't stick to the tray once it was ready; this was a good thing because it came out easily because I had

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  • Subject: Design & Technology
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Unit 3 - Impact on Information Availability

Task One - Impact on Information Availability What electronic information do I access and what impact has this had on my life The internet has had a huge impact on people's lives throughout the world, it allows people from all over the world to communicate and meet in one place, and the impact is clearly visible in today's society. Originally used for communication and business the internet has quickly grown and everything can now be found on the internet quickly and easily. Personally, the internet plays a big part in my life as it is easy to find any information that I may require. It assists me in my school work and revision with sites like BBC Bitesize set up with revision resources and links to other helpful sites. I also use the internet for the latest news (and weather) using sites such as BBC News which contain all the days main headlines as well as discussion by the public on these stories. More recently I have been using the internet for online shopping, which is particularly helpful for events such as Christmas, with sites like Amazon and Play supplying goods for cheaper prices than most high street retailers as well as quick and efficient delivery. All of these websites listed are everyday sites which I use as helpful aids in my life, but I also use the internet for my interests and hobbies. I frequently visit sites such as Skysports to check all the latest

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  • Subject: ICT
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Evaluate the arguments for and against UK entry into the eurozone.

Claire Reilly The New Europe: Understanding the European Union -Evaluate the arguments for and against UK entry into the eurozone. The debate over the United Kingdom's involvement in the eurozone has been prominent ever since the British government decided to withhold UK entry until a later date. Although the euro only became a physical reality across Europe on 1 January 2002, it has been years in the making. The development of the euro dates back to the Treaty of Rome in 1957, when a common European market was declared as a European objective, aiming to increase European prosperity and develop an even closer relationship amongst the peoples of Europe. Following agreements such as The Single European Act (1986) and the Treaty on European Union (1992), the European Monetary Union, EMU, has been introduced, laying the foundations of the single currency. The European Central Bank (ECB) was established on 1 June 1998. It is based in Frankfurt am Main, Germany, and aims to maintain price stability and to conduct a single monetary policy across the euro area. This is done through its own activities and through working with the national central banks. Together, the ECB and the euro area national central banks are known as the Eurosystem. On January 1 2001, the exchange rates of the participating countries were irreversibly set. Member states implemented a common monetary

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Compare and contrast the Functionalist and Marxist views of society.

Compare and contrast the Functionalist and Marxist views of society. Sociology has been classified as the last in a long line of emerging scientific disciplines which people have developed and explored in order to make sense of their world. Early theories such as the positivist approach of Comte, the functionalist views of Emile Durkheim and the conflict perspectives of Karl Marx have offered a view of why human beings behave as they do and how they fit together in society. Each theory has to some extent been shaped or influenced by the approach of others and many sociological explanations have comparisons or contrast that can be made. Browne once said "sociological perspectives centre on how much freedom or control the individual had to influence society" He goes on to comment on the two main approaches "structuralism is concerned with the overall structure of society and the way social institutions act as a constraint, or limit and control individual behaviour". Structuralism offers a view of the individual being controlled by the society they live in, Marx and Durkheim are similar in that they can both be described as structuralists, however their individual ideas are somewhat different. Functionalism was developed by Emile Durkheim, he believed like Comte that sociology should be viewed as a precise science and that society should be studied objectively. Durkheim

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Mcdonalds Marketing Mix

The Marketing Mix and Its Constraints McDonalds - the marketing mix is applied to products in McDonalds in many ways: McDonald's are looking at different ways of saving energy and the planet. One way was that they collected waste from eleven of their restaurants where it was later collected and recycled to produce electricity for local buildings. A McDonald's spokesman said the experiment had cut its carbon impact by fifty four percent in Sheffield. Mc Donald's became the first fast tune chain serving coffee from ethical sourced growers. The deal for the fair trade coffee from South and Central American farms has been certified by the rainforest alliance. Product: Menus give customers a choice of what they want to order/eat. Therefore McDonalds develops menus on what customers want to gain maximum profits. The company gains such information after going through the process of market research. However the customer's requirements change over time. To keep customers happy and the company up to date with customer's needs and wants, the company should monitor customer's preferences. In order to meet these changes, the company introduce new products and phase out old ones, this will continue over time. The company know that items on the menu will vary in popularity. Their ability to generate profits will vary at different point in the products life cycle. All products

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