Should everyone be to taking statins to reduce the risk of cardiovascular disease? Cardiovascular disease is one of the biggest killers of the modern world. Approximately 70,000 people die from cardiovascular disease or its complications every year in the UK alonei. Worldwide it claims over 17.1 million lives a yearii. Although CVD is a multi-factorial disease with many preventable and non-preventable causes, studies have shown that there is a high correlation between high LDL levels and the incidence of CVDiii. Statins are a group of drugs designed by the pharmatsuitical industry to reduce levels of LDL in one's blood. Low density lipoproteins are protein molecules made up of both triglycerides and cholesterol. Cholesterol is a sterol which means in it insoluble in water. In order for it to pass through the blood stream and diffuse through cell membranes it needs to be attached to a soluble chain molecule such as a triglyceride. Most cardio-vascular events start with the formation of an atheroma, which is an acculmation of fatty deposits in the artery walls between the inside of the artery (lumen) and the elastic muscle layer. An atheroma can lead to the narrow of the lumen in a process called stenosis which increases the patient's blood pressure. The blood constantly hitting the atheroma as it juts out into the lumen can cause it to harden. Often this leads to a
THE EFFECTS OF CAFFEINE CONCENTRATION ON DAPHNIA HEART RATE AIM The aim of this experiment is to research on the effect caffeine has on Daphnia heart rate. To enable this, a certain percentage of caffeine solution was tested on Daphnia (water fleas) as it will be a lot easier to monitor their heart rate due to their translucent body. This practical will help develop data representation and improve key practical skills. INTRODUCTION Caffeine is an odourless, slightly bitter alkaloid found in coffee, kola nuts and small amounts of cocoa. In humans, Caffeine acts as a stimulant on the central nervous system preventing drowsiness temporarily in order to keep the brain 'alert'. Caffeine is one of the world's most popularly used drugs and acts a mild diuretic in humans and animals. It will be unethical to carry out this experiment on humans as they have a high level tolerance to caffeine as it was proven in a recent experiment that higher concentrations of caffeine solution causes the heart to beat abnormal fast so an alternative source. Daphnia will be used to carry out this investigation as their resting heart rate is very high and this will air to provide rapid results. .1. Diagram of a typical Daphnia Daphnia are small water crustaceans which share a slight resemblance to water fleas and are mostly found in lakes and ponds. Food sources and beverages containing caffeine
Global climate change. Greenhouses gasses that warm the earths surface are water vapor, carbon dioxide, and methane. When light from the sun reaches earth, it is reflected back into the earths atmosphere as infrared radiation.
Cesar Martinez Dr. Coburn Bio 1 T/TH October 26, 2009 Global Climate Change According to an article by the British Broadcast Corporation (BBC), the United States emits more greenhouses gases per person then any country in the world. Although greenhouse gases occur naturally in the earth's atmosphere, humans have rapidly increased the amount of carbon dioxide (CO2) in it. All the excess carbon dioxide has caused a gradual increase of the earth's temperature, which we call global warming. Scientists believe global warming is most likely caused by human. Although many people think global warming is not real, I believe global warming is the most important issue facing the world. The burning of fossil fuels and deforestation are the main causes for global warming. The effects of these could have a devastating effect on earth. Effects like the spread of disease, drought, extreme weather patterns, and even the extinction of animals. There are many changes we can make to combat global warming like using alternative fuel sources like nuclear, solar, and hydrogen. Greenhouses gasses that warm the earth's surface are water vapor, carbon dioxide, and methane. When light from the sun reaches earth, it is reflected back into the earth's atmosphere as infrared radiation. Once infrared radiation is reflected back into the atmosphere, greenhouse gases absorb the radiation and reflect it
Threats to Marine Turtle Survival The Problems, Risks to Turtles and Examples Today the seven species of marine turtle that swim our oceans are all included on the World Conservation Union's (IUCN) Red List of Endangered Species . Before human intervention, it was thought that only one in one thousand turtle eggs actually survived to become adults. With human as well as natural threats, it is estimated to be up to one in ten thousand . Figure one clearly illustrates how the number of leatherback turtles nesting has fallen in Playa Grande and Ventanas, popular tourist destinations. There has been 95% decrease in the number of female leatherbacks between 1988 and 2002 and there are multiple reasons that have contributed to such a steep fall. This report will concentrate on tourism related threats. Unfortunately human threats now add to threats posed by nature and if it was not difficult enough to survive before, turtles now have to contend with problems we create. Marine turtles breathe with lungs. This forces them to surface in order to inhale air. The heart (see figure 2) consists of two atriums but one ventricle and results in an incomplete double circulatory system. This allows them to bear high levels of carbon dioxide in the blood. Blood and muscle tissue can accumulate large quantities of oxygen. These features allow turtles to stay underwater and sleep for up
In my science general coursework I will be answering the question "What happens to the energy in a bouncing ball?" We all know that when we drop a ball from a height it wont bounce back to the original drop point, but do you know why? This must mean that the amount of energy it started off with is lowered. Where does that energy go? These are all the questions I will be answering by using sources such as textbooks and notes, the marking grid, books in library and the internet. My method for collecting data was very simple. I used two one metre rulers and a tennis ball! By dropping the ball from a range different heights I could put the data into a graph and see if there was a relationship. To make it a fair test I used the same ball on the same surface and whether it was dropped from the top of the ball or the bottom of the ball. It is very easy to make mistakes on such an experiment, it is all done by eye and reaction times so it is not the most precise of methods. To make my data more precise and reliable I carried out the test 4 times and erased any anomalies in my data. Then I averaged the data to get a reasonably accurate graph which showed a visible relationship. I am measuring the mass and the height so I can investigate why there is a loss of energy in the ball as it bounces back. Page 1 Bounce height (m) gravitational potential energy (j) original height
Sir Arthur Conan Doyle's stories about the fictional detective Sherlock Holmes have been popular since they were first published in 1886. Explore the reasons behind this enduring popularity?
Report of My Visit to Xscape On the 6th of February 2004, our Physics class was invited to take a tour of the skiing facility at Xscape in Milton Keynes. The visit gave me a good insight into different areas of Physics that were seen at the skiing complex. We learnt a lot about the cooling system, how it works, and areas of energy loss which could be harnessed instead of lost. We were given a tour as well as a brief talk about Xscape by Mr. Shears. Section 1: Aspects of Physics Observed .1 I observed the operation of drag lifts at Xscape which took skiers back up the ski slope. Each drag lift consisted of 16 hangers onto which the skiers would sit on when going up the ski slope. The cable used to carry all 16 skiers needs to be able to support the 16 skiers by withstanding high degrees of tension. This tension acts on the cable in opposite directions, but these tensions will not equal each other. This is explained below: I am going to focus on the tensions in the cable for one skier sitting on a hanger being pulled up the ski slope. We were told by Mr. Shears that the cable to the top of the slope is at an angle of about 22° to the horizontal and the cable down to the bottom of the slope was at about 20°. We can find the tensions in the cable by resolving forces acting horizontally and vertically on the cable. We know that the horizontal component of T1 and T2 must
Medical research may be carried out on transgenic organisms to obtain information which can improve medical knowledge. For example, oncogene which causes cancer in humans can be inserted into mouse,
THE ROLE OF TRANSGENIC ORGANISMS CAN ONLY BENEFIT HUMANS. A transgenic organism is an organism whose genome has been modified or genetically manipulated by the introduction of a foreign gene. The first transgenic animal was produced in 1982, when a growth hormone from a rat was inserted into a mouse. Since then, genes from different species, including humans, has been introduced into animals, plants and even micro-organisms. (http://nabc.cals.cornell.edu). Genetic engineering provides an alternative to traditional methods of plant and animal breeding because it is a lot faster and efficient. Medical research may be carried out on transgenic organisms to obtain information which can improve medical knowledge. For example, oncogene which causes cancer in humans can be inserted into mouse, forming a transgenic organism called Oncomouse. The mouse develops tumours and is used in cancer research to find possible drugs for the disease (Biological science D. Taylor). Scientists are also finding ways to produce proteins or drugs in transgenic animals. Milk-producing transgenic animals like cows are especially useful for pharmaceutical medicines. Transgenic animals like pigs may also be designed for organ production, helping to reduce the shortage of kidneys and livers available for transplants. Genetic engineering can help to increase crop yield by developing transgenic organisms
NAME: FARAH NADZIRAH ROSLI CLASS: ALM 7 M 13 Title: Using Different Carbon and Source for Growth Objective: To investigate the effect of using different carbon source on the growth of yeast cells. Background summary: Growth depends upon both the type of the nutrients available and their concentration. Cells are largely made up of the four elements: carbon, hydrogen, oxygen and nitrogen with smaller, but significant, quantities of phosphorus and sulphur. Accounting as they do for 90% of the cell's dry mass, all six elements are essential for growth. Hence, like all living organisms, microorganisms require an energy source, a carbon source and a range of nutrients for metabolic and cell growth. Microorganisms are small, easily dispersed and quick to multiply given a suitable environment. They grow on a wide diversity of substrates making them ideal subjects for commercial application. The microorganisms need organic carbon source, such as carbohydrates, as most of them are heterotrophic. Carbohydrates act as a respiratory substrate of cells. Microorganisms also need a nitrogen source for synthesis of DNA, RNA, ATP, coenzymes and chlorophylls. Apart from that, each species has its own optimum conditions within which it grows best. Respiration involves a series of metabolic pathway, which is a series of enzyme-controlled chemical reaction, where the product of
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
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