To determine the water potential of a potato tuber cell using varying salt solution.
Aim To determine the water potential of a potato tuber cell using varying salt solution. Introduction Osmosis is the diffusion of water molecules from a region where it has higher water potential to a region where it has lower water potential through a partially permeable membrane1. As osmosis is a type of diffusion the same things that affect diffusion have an effect on osmosis some of theses things are: * The concentration gradient - the more the difference in molecules on one side of the membrane compared to the other, the greater the number of molecules passing through the membrane and therefore the faster the rate of diffusion2. * The surface area - the larger the area the quicker the rate of diffusion * The size of the diffusing particles - the smaller the particle the quicker the rate and polar molecules diffuse faster than non-polar ones3. * The temperature - the higher the temperature the more kinetic energy the particles have and so the faster they move. From the diagram4 we can see the process of osmosis in a simple expression. On the right side there is pure water, which has the maximum water potential of 0. Water potential is the pressure created by water. As you can see from the diagram the pure water is pushing its way through the semi permeable membrane at a high pressure. This is its water potential. Water potential is measured in kilopascals (kPa)
To what extent will does correlation and extrapolation assist Nintendo in forecasting sales?
To what extent will does correlation and extrapolation assist Nintendo in forecasting sales? (34 marks) Correlation is the relationship between two variables. Extrapolation is related to correlation, as it involves plotting a linear regression curve (also known as a line of best fit) which is based upon how two variables are correlated, and extending the line to predict future values. For Nintendo, a computer game and console manufacturing company, a common example would be the relationship between the level of advertising expenditure and the effect of this on sales of its products. The graph to the left shows a strong positive correlation between sales and advertising, meaning if Nintendo increases its advertising, they can expect to see an increase in sales. Because all values are close to the line, as advertising expenditure increases on the x-axis, sales on the y-axis increase proportionately. The regression line can be extended past the '80' figure (meaning £80million) to predict what sales will be like if they spend £100million or even £900million. The uses of such analysis to Nintendo are to an extent very valuable. By creating a scatter graph like the one above, Nintendo can spot trends and forecast future events. For example, they could estimate demand at a certain point in the coming year. One would expect demand to surge at Christmas time when people are
paper cones investigation
Investigation Report Aim Theory When an object is dropped in air, it accelerates. If it is allowed to drop far enough then it can reach its terminal velocity. This is the maximum velocity of the object during its fall and occurs when the upward force of air resistance acting on the object equals the weight of the object. So at terminal velocity... (P.31, Complete Physics, 1999, Pople, Oxford University Press, ISBN 0-19-914734-5) (P.33, Physics 1, 2000, Cambridge University Press, ISBN 0-521-78718-1) Looking for a formula for air resistance... F = force of air resistance ? = density of air = 1.2kgm-3 c = coefficient of drag for the object / dimensionless A = cross-sectional area of object hitting the air / m2 v = velocity of the object / ms-1 (http://damonrinard.com/aero/formulas.htm) Looking for a formula for the weight of an object... W = m.g W = weight / N m = mass / kg g = acceleration due to gravity, 9.81Nkg-1 (P.55, Physics, 1991, Robert Hutchings, Nelson, ISBN 0-17-438510-2) So putting these formulae together... From the Physics AS course, v = velocity x = displacement t = time so References to the specification Forces and Motion 2821 Forces, Fields and Energy 2824 Aim of your investigation The aim of this work is to investigate the relationship between the time taken for a paper cone to fall and the mass of the cone. Variables
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
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
You have been stranded on a desert island. Describe your first 24 hours alone on the island.
Hannah Greenslade Y10 Coursework Assignment 2 5/11/01 Option 3 Task; You have been stranded on a desert island. Describe your first 24 hours alone on the island. The first thing that hit me was the smell. Even before I opened my eyes, I knew where I was. The tantalizing scent of washed-up waves and bananas all rolled into one. I felt the millions of grains of sand, hot against my fingers and the cool breeze against my face, - a relief from the sweltering sun. I heard the sea crawling onto the sand and, further away, the same monster dashing against the rocks. As I opened my mouth to take in a gulp of air, I tasted salt in my throat. Not the same taste as on Brighton Pier, when you look over into the sea, but a fresh, clean one, as if taking in pure oxygen. Only then, when my four other senses had taken in their share of my surroundings, did I allow myself to open my eyes. I was amazed at how easily fantasy and reality intertwined at that moment. It was like continuing a dream after waking up. As I lifted my eyelids, as the barrier between my imagination and actuality was removed, the accuracy of my prediction astounded me. As I sat up and looked around, I realized that I must have been asleep for a long time, as my sopping wet clothes were completely dry. I could just see the island on which I had been staying, a strip of land on the contrasting horizon. The rubber
Tennessee Williams wrote in a letter that It (Streetcar) is a tragedy with the classic aim of producing a catharsis of pity and terror and in order to do that, Blanche must finally have the understanding and compass
Tennessee Williams wrote in a letter that "It ('Streetcar') is a tragedy with the classic aim of producing a catharsis of pity and terror and in order to do that, Blanche must finally have the understanding and compassion of the audience. This without creating a black-dyed villain in Stanley. It is a thing (misunderstanding) not a person (Stanley) that destroys her in the end." In your opinion, to what extent has Williams succeeded in his aims. Although there are many different viewpoints on a conventional tragic heroine, Aristotle made his views clear that a hero must fall from fortune and power, due to a tragic flaw, allowing an audience to feel catharsis at the end of the play. It can be argued that Stanley causes Blanche's downfall, however, it is clear that Blanche had brought this upon herself by creating a conflict between them and ensures her own downfall by other means such as her promiscuity and flux into fantasies. Williams makes it clear that a misunderstanding destroys Blanche in the end. This misjudgement can be seen in her aggressive teasing of Stanley and her uncomfortable belonging in multi-cultural New Orleans. From the beginning of the play, Williams makes it clear that 'the Kowalski and the DuBois have different notions' with Blanche withholding the Southern Belle attitude of 'Belle Reve'. However, it is clear that Blanche cannot cope with the stark
Experiment to determine the ethanol content of wine
Experiment to Determine Ethanol Content of Wine The purpose of this experiment is to determine the ethanol content of each of the wines and compare the value determined to the value quoted on the label. These results can then be used to conclude which region is more accurate in quoting the value of the ethanol content of the wine. This experiment takes advantage of the fact that ethanol is less dense than water in solution. The density of ethanol at 20°C is 0.789 g/cm3 while the density of water at the same temperature is 0.998 g/cm3. It then follows that different solutions of ethanol and water will have different densities also, because the relative volume of ethanol increases and water decreases so the density of higher percentage ethanol solutions will be less than the density of lower percentage ethanol solutions. This occurs because water molecules are much smaller than ethanol molecule, meaning more water molecules can "pack" into a smaller volume than ethanol molecules, meaning there is more mass per unit volume of water compared to ethanol, meaning it has a higher density. In this experiment, solutions of ethanol in water were made up, going from 0% to 20%. These were then weighed, and the density of the ethanol was calculated. From this, a graph of percentage ethanol solution against density was made. This graphs later compared to the density of the wine, so
How the structure of cells is related to their function.
How the structure of cells is related to their function. All living things are made up of cells, whether its plants, humans or even bacteria. There are two different types of cells one is the prokaryotic and the other is the eukaryotic. The name cell was used by an English man who in 1665 use the first microscope and reported seeing what he described looked like the sleeping chambers in the monasteries that were called cells, in a piece of cork.1 The first of the two types is the Prokaryotic cell, the pro meaning before the nucleus as this cell has no true nucleus.2 Prokaryotic cells are surrounded by a cell wall and a cells membrane, and in some ways this makes them similar to a plant cell which is eukaryotic, but they have no nucleus or organelles inside, but they do have flagella's and cilia on the outside. The flagellum is a long whip like tail attached to the end of the prokaryotic cell which helps with its movement. The cilia are small spiked hairs that help to transport fluid in and out of the cell and for protection against harmful substances. They are also found in abundance in the eukaryotic cells in the human trachea where they collect dirt, they either by moving it down into the stomach or push it back up into to the mouth to spit it out.3 One of the most common prokaryotic cells would be bacteria, they are the smallest cellular organism, and each human being
Estructura de las grandes disqueras.
Las Disqueras (internacionales): Estructura de las grandes disqueras: La producción musical es una actividad sumamente compleja. Hay que componer las canciones, tocarlas, grabarlas, mezclarlas y masterizarlas, promover el disco, hacerle publicidad y, por último, hay que venderlo. Para poder hacer todo esto de manera eficiente las compañías discográficas están estructuradas en diversas divisiones y departamentos. Las grandes corporaciones del mundo del entretenimiento (Sony, Universal, EMI, AOL- Time Warner y Bertelsmann Music Group) poseen, cada una, un conglomerado de empresas subsidiarias y asociadas, muchas las cuales son sellos disqueros que, a su vez, tienen a otros sellos de menor envergadura asociados a ellos, etc. Esta cadena puede llegar a ser realmente larga, pero en términos de estructura organizacional son los grandes sellos disqueros lo que se encargan de mercadear y vender los discos de los sellos más pequeños. Las grandes corporaciones del entretenimiento están organizadas como cualquier otra corporación: tienen un CEO, un COO, un CFO etc. Luego, cada gran sello disquero que pertenezca a la corporación, tiene un presidente. Por ejemplo, en AOL- Time Warner hay un presidente para Warner Brothers Records, otro para Reprise Records, otro para Atlantic Records etc. Debajo de los presidentes de las disqueras se encuentran los vicepresidentes,
