In what ways do lipids differ from carbohydrates?

A. In what ways do lipids differ from carbohydrates? Lipids are a group of substances, which include fats, oils and waxes. Carbohydrates include sugars, starches, glycogen and cellulose. They are stored in plants as starches and in animals as glycogen. There are many differences between carbohydrates and lipids. For example lipids are insoluble in water whereas carbohydrates are soluble in water. This is because lipids contain non - polar hydrocarbon units whereas water contains polar hydrocarbon units. So when the two are mixed together there is no attraction between particles so no breakdown is possible. But lipids care soluble in non - polar solvents, e.g. alcohol. Carbohydrates have polar hydroxyl groups, so there are able to break down in water. The structure of each is also different. Carbohydrates form long chained polymers and lipids form shorter chains of polymers. Also they belong to different groups; lipids belong to the Ester group and carbohydrates belong to the Keto and Alcehyde groups. In carbohydrates the ratio of Hydrogen to Oxygen atoms is always 2:1, but there is not a fixed ratio of these elements in lipids. They also vary in the amount of energy they release when oxidised; lipids release large amounts whereas carbohydrates release a lot less. B. Using examples to illustrate your answer, describe the functions of lipids in organism. Lipids are a useful

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  • Level: AS and A Level
  • Subject: Science
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Investigation in to what happens to the resistance of a thermistor as its temperature changes.

Physics Coursework Danielle Roots Mr Small Aim: To investigate what happens to the resistance of a thermistor as its temperature changes. What is a thermistor? Is a resistor that changes in resistance with temperature. "Its principle characteristic is that their electrical resistance changes in response to changes in their temperature." http://www.betatherm.com/therm_theory.html Symbol for a Thermistor: Calculating resistance Resistance in a circuit can be calculated using the levels of voltage and current in a wire or a single component. The formula we use to measure resistance is: RESISTANCE = VOLTAGE R = V CURRENT I What is Current? Current is the flow of electrons around an electric circuit. It is measured in amps. Current is measured in Amps. amp = 1 coulomb per second Per means divided by so current = charge time What is resistance? Resistance is the measure of how much the current is slowed down. The bigger the resistance, the smaller the current. Resistance is measured in Ohms (symbol ?). What Causes Resistance? [ Parallel Circuits Series Circuits Only has one path for the charges to move along. Charges must move in "series" first going to one resistor then the next. If one of the items in the circuit is broken then no charge will move through the circuit because there is only one path. There is no alternative

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  • Level: AS and A Level
  • Subject: Science
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To Determine the Focal Length of a Convex Lens.

To Determine the Focal Length of a Convex Lens. Aim: To determine the relationship between the power of the vocal lens, object and the image distance from the lens. Apparatus: Bulb Projector Convex lens Lens holder Screen Optical Bench 12V power supply Diagram: Method: * Set up the apparatus as shown in diagram. * Put the focal lens at the first distance shown on the results. Also put the object at the 0 point of the optical bench. * Switch the 12V bulb and move the projector until a clear picture of the object is visible. * Record the results on the results table of the distance from the lens to the projector * Keep on moving the object to the 6 points shown on the results table and record the distances when object is visible for each measurement * I will do the experiment twice for each measurement to ensure that the results are accurate Safety: Making sure that all bags are put under tables will make this experiment safe. Also the work surface will be cleared of all books and other mess, which will mean that the table will be empty and easier to work on. The bulb will be hot so I will make sure that no one touches it or looks directly at it because it will also be very bright. Theory: The distances from the lens to the screen (U) as well as measuring the distance from the lens to the projector (V) will make me think of a formula. I have obtained a

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  • Level: AS and A Level
  • Subject: Science
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Analysis of dog genome assists the understanding of human health

Analysis of dog genome assists the understanding of human health Ever thought of how resembling and how close you and your pet dog can be? Dogs not only share the same air, same water, the same house or even the same bed with humans (Clarke, Toni.2005), they also exhibit similarities in genes and diseases with humans. Here are some examples of numerous diseases that we share with dogs: Cancer, deafness, blindness, heart disease, epilepsy etc. Scientists therefore believe that decoding dog's genome will provide helpful information in developing cures for the diseases in both species. Much work has been done over the past few years to discover which specific gene on a particular chromosome is responsible for a special type of disease. The Dog Genome Project is currently the most popular program carried out at The Broad Institute of MIT and Harvard, which is "part of the National Human Genome Research Institute's Large-scale Research Network" (National Institutes of Health, 2005). Fred Hutchinson Cancer Research Centre was initially involved, now taken over by the NHGRI. This project is applied by scientist as the model system and aims to map and clone the genes of dogs in order for research in cancer and genetic work. Gene mapping is the process that centres the whole genome project. This practise is defined as "the determination of the sequence of genes and their relative

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  • Level: AS and A Level
  • Subject: Science
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In this coursework I am going to investigate the different characteristics of cloning, how it came to be, the methodologies and how it works, and, in the process, determine its significance to humans.

The importance of cloning In this coursework I am going to investigate the different characteristics of cloning, how it came to be, the methodologies and how it works, and, in the process, determine its significance to humans. Introduction There are several meanings being attached to cloning today and they cause confusion and uncertainty. However, the general definition that most scientists use in describing cloning is the one that is relevant to the different processes for duplicating a biological material. Hence, the definition covers both the artificial and natural processes. Cloning by artificial means is the one most popularly identified with cloning: It is the creation of a clone scientifically, that is, by some conscious design or human interruption. Contrary to widespread belief, cloning can be considered a natural process, too. Natural cloning has been going on for billions of years. Natural cloning occurs when an organism reproduces asexually or when two genetically identical twins are produced by a splitting of a fertilized egg. For example, when one takes a stem from a yam plant and plant it in the ground, a new plant would grow as it takes root. The new plant can be considered a clone in the sense that it is identical to its parent. Similar cloning takes place in grass, potatoes and onions. This is a technique for producing plants asexually. Humans have been

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  • Level: AS and A Level
  • Subject: Science
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Describe the main strengths and weaknesses of Utilitarianism

Describe the main strengths and weaknesses of Utilitarianism Utilitarianism is an idea first developed by David Hume in his book 'Why Utility Pleases'. Hume tried to account for the fact that we tend to approve those qualities and actions that are useful to society; that is, those that promote social utility. However, Hume's theory of ethics could not be described as utilitarianism in the way that the term is used today. Jeremy Bentham was the first person to use Utilitarianism in the way in which the term would be used today. Drawing on and adapting Hume's ideas in order to coincide with the society in which he lived during the industrial revolution. He was concerned with social reform as the conditions in which people lived and worked were appalling. Bentham wanted to find a way of defining right and wrong without a need for a transcendent authority. In 'Introduction to the principles of moral legislation' he tried to establish a way of arguing for something to be good and bad according to its benefits for the majority of the people, he called this the principle of utility. Bentham established a Hedonic calculus by which happiness could be measured, the hedonic calculus was split up into six categories; duration, intensity, remoteness, purity, richness, and extent. Using this calculus, Bentham believed that it was possible to measure the amount of pleasure or pain

  • Word count: 558
  • Level: AS and A Level
  • Subject: Science
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Setting up a Light Microscope.

Setting up a Light Microscope Aim: To set up a Light Microscope Microscopes came into existence in 1670. It was a man called Antoni Van Leeuwenhoek who came up with this innovative idea of inventing a Microscope. Soon his invention was very popular. Scientists everywhere started to utilize similar microscopes. Microscopes have been an asset to the scientific industry. We nowadays use microscopes to things in a greater detailed picture. The naked eye cannot see an onion cell, to observe the onion cell we need to use a Light Microscope. When using a Light Microscope we can adjust the magnification to what we desire. A light microscope is an excellent piece of equipment to use when distinguishing between an animal and plant cell. There are many types of microscopes. Two common microscopes are the Light Microscope and the Electron Microscope. Electron Microscopes are those that are used in big science laboratories. They can magnify up to a huge 500,000x. Whereas, a standard light microscope can only magnify upto 1000x. There is also a massive price difference between the two microscopes. An Electron Microscope can cost up £2.5 Million and a good light microscope will only cost about £50. Method You have to be very careful when using a light microscope. Follow these i9nstructions to setup and use the microscope properly. * First of all place the microscope in the

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  • Level: AS and A Level
  • Subject: Science
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A2 OCR B Advancing Physics Coursework - Research and Report - The development of a Theory of Gravity

The development of a Theory of Gravity. What's behind it and where does it stand in relation to the other forces? Abstract: The Theory of Gravity has been transformed through the last century, from an original and important classical framework to more recent relativistic and then quantum interpretations, eventually culminating in a specific requirement to link it all together with the other forces and create a unified theory of everything. The search for unification is currently very much dependent upon experimentation and raises questions as to the scientific validity of String Theory and whether it exists as science or philosophy - or indeed just an elegant, but meaningless, example of mathematical aesthetics. . Introduction The ultimate goal for physicists is to devise a unified theory, which describes the universe all in one go. However, this proves difficult - there are partial theories which do not fit together, each predicting a limiting number of observations and neglecting others. Nevertheless the Standard Model exists as a framework for the coming together of partial theories. .1 The Basics of the Standard Model In matter there appears to be four basic forces at work. Gravity is the weakest of the four but acts over great distances, binding stars and galaxies together. The electromagnetic force is stronger and is responsible for holding atoms and molecules

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  • Level: AS and A Level
  • Subject: Science
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Why are fossil fuels so important to society, and why do we need to develop renewable fuels for the future?

Why are fossil fuels so important to society, and why do we need to develop renewable fuels for the future? Fossil fuels are substances, which were created several hundred million years ago through the decomposition of prehistoric organisms and plants. Machines such as televisions, cars and computers we take for granted in our daily lives, need energy to run. The energy used to power these energy things come from fossil fuels. Fossil fuels can be categorised into three types; petroleum, natural gas and coal. Examples of petroleum fuels include gasoline, kerosene and diesel fuels. Because of petroleum's importance to our energy needs, infrastructure necessary to extract oil from the ground and refine it is already in place, and this oil is relatively economical source of energy. One of the major forms of natural gas is propane, which is also useful in a number of applications, including transportation. We burn natural gas to heat our homes, hot water and for industrial processes. Another form of fossil fuel is coal. Coal occurs naturally in a solid form and is used primarily to produce electricity. It therefore provides us with light, motive power from electric motors, and our many electronic devices. At some point in the future, certain countries will invariably be without a fossil fuel- based economy as fossil fuels are not renewable, but rather an expendable source of

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  • Level: AS and A Level
  • Subject: Science
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Chem Lab report. Standardization of hydrochloric acid by sodium carbonate solution

Laboratory Report: Experiment 1 Standardization of hydrochloric acid by sodium carbonate solution Name: Cheung Chun Hin, Harry Class: 6L (12) Date: 11-9-2009 Objective: To determine the concentration of hydrochloric acid using sodium carbonate solution as a primary standard in volumetric analysis (acid-base titration) Principle of method: The concentration of the hydrochloric acid can be determined by the titration reaction between hydrochloric acid and sodium carbonate solution. Na2CO3 (aq) + 2HCl (aq) H2O (l) + CO2 (g) + 2NaCl (aq) From the above equation, We measure the volume of hydrochloric acid used in the titration (the difference of reading on the burette) and use it in calculating the concentration of hydrochloric acid. So the molarity of the hydrochloric acid Procedures: . The mass of anhydrous sodium carbonate required was weighed to prepare 250.0 cm3 of 0.05M sodium carbonate solution. 2. All anhydrous sodium carbonate was dissolved in a beaker with a suitable amount of deionized water and the mixture was stirred. 3. Sodium carbonate solution was poured into a 250.0 cm3 volumetric flask and it was made up to the graduated mark using deionized water. 4. The volumetric flask was shaken upside down for several times. 5. 25.0 cm3 of sodium carbonate solution was pipetted into a conical flask. 6. 3 drops of methyl orange indicator was added into the

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  • Level: AS and A Level
  • Subject: Science
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