ATP or Adenosine Triphosphate.

ATP stands for Adenosine Triphosphate and is the immediate supply of energy for biological processes. The ATP consists of an organic nitrogenous base, Adenosine, which is one of the four bases found in a DNA strand, it also consists of a ribose sugar with three phosphates joined by high energy bonds. The energy itself is stored in the form of high-energy chemical bonds; this energy is released on hydrolysis, i.e. by the reaction with water, in a similar way peptide bonds are hydrolysed in proteins. ATP is adapted to is highly suited to its function and role within living organisms as it is easily broken down and is thus a store for immediate energy; it is also a small molecule and can easily move around cells and through membranes. The production of ATP is usually associated with two principalities including respiration and mitochondria. It is common knowledge that respiration, which happens in all living organisms, produces energy and is expressed by the equation of: Glucose + Oxygen Carbon Dioxide + Water + Energy Respiration can be, aerobic, occurring in an oxygenated environment or anaerobic, occurring in oxygen lacking environments. The latter producing 2 molecules of ATP and the former producing between 36- 38 ATP molecules. The energy released from the respiration of glucose is used to add inorganic phosphate to ADP, producing ATP. This is achieved by glycolysis,

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To investigate the energy content of different foods.

Food for fuel Aim: To investigate the energy content of different foods. Introduction: We can show that food is a fuel by burning it, using this, we are going to investigate the energy content of four different foods; peanut, bread, pasta and a Brazil nut. Food is also a fuel in another sense. Plants and animals use food to get their energy. Different foods contain different types and amounts of energy. When food, and all other fuels (e.g. coal, oil, etc.), is burned, energy in the form of heat is transferred to it's surroundings warming them. The body's most basic need is for energy. To get energy it needs food as a fuel and oxygen to burn it. The amount of energy foods can produce is measured in units called calories. A food calorie, or kilocalorie, is the amount of heat required to raise the temperature of 1 kilogram (2.2 pounds) of water 1 degree Celsius (1.8 degrees Fahrenheit). The body changes the calories in food into energy, which is necessary for every act from blinking an eye to running a race. Energy is also used for the growing process, for rebuilding damaged cells, and for regulating body systems. The number of calories needed each day depends upon how much energy an individual's body uses. An active child can need more calories than an adult who works at a desk. The body needs more calories in cold weather to stay at an even temperature.

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Succession is the progression of plant and animal species in an area from smaller simpler organisms to larger more complex organisms, eventually leading to a climax community.

Succession Introduction Succession is the progression of plant and animal species in an area from smaller simpler organisms to larger more complex organisms, eventually leading to a climax community. The climax community is reached when the species found in the area remain constant over time with few or no species being wiped out or starting to grow- there is an equal balance between births and deaths and gross primary productivity is the same as total respiration. The climax community exists as long as biotic and abiotic factors allow. Things which could devastate a climax community include forest fires and drastic changes in climate, or biotic factors like Dutch elm disease, a fungus transmitted by European and American bark beetles which killed millions of elm trees in the 1980's. The climax community arises in stages called seral stages. There are two types of succession, primary and secondary. Primary succession A primary succession is one that takes place in an area or piece of land which was not previously populated by other organisms. Examples of places where primary successions can take place include newly bared rocks, sand dunes, river deltas where fertile silt is deposited, hardened lava from a volcanic eruption or in a freshwater lake. A xerosere is the name given to a succession which begins on dry rock and the plants which grow there are called

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The effect of caffeine on the heart rate

The effect of caffeine on heart rate Aim: To investigate the effect of caffeine on the heart rate of Daphnia (water fleas). Introduction: Plants produce caffeine as an insecticide. Cocoa in South America, coffee in Africa and tea in Asia have all been used for hundreds of years to produce 'pick me up' drinks containing caffeine. These days, caffeine is also used as a flavour enhancer in a wide range of cola and other soft drinks. In addition, it has medicinal uses in aspirin preparations, and is found in weight-loss drugs and as a stimulant in students' exam-time favourites like Pro-plus and Red Bull. In humans, caffeine acts as a stimulant drug, causing increased amount of stimulatory neurotransmitters to be released. At high levels of consumption caffeine has been linked to restlessness, insomnia and anxiety, causing raised stress and blood pressure. This can lead to heart and circulation problems. Daphnia are small, planktonic crustaceans commonly called water fleas because of their saltatory swimming style (although fleas are insects and thus only very distantly related). They live in various aquatic environments ranging from acidic swamps to freshwater lakes, ponds, streams and rivers. Hypothesis: Caffeine will increase the heart rate of the Daphnia (water fleas). Equipment needed: * Culture of Daphnia (water fleas) * Cavity slides * Dropping pipettes *

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The Role of ATP

The Role of ATP Living organisms all need energy to live, for reproduction and for movement. This energy is used in the form of adenosine triphosphate (ATP). It is known as the 'energy currency of living organisms' and can be produced by two methods: . Photosynthesis 2. Chemical Energy Photosynthesis is the absorption of light energy from the sun, which is then transferred into chemical energy. It occurs in plants and results in a useful supply of carbon. Chemical energy is acquired from a 'ready made' source of carbon such as biological materials found in plants and animals, although this energy still originally comes from the sun. ATP * One molecule can contain large amounts of energy which can be used very easily. * ATP is not a storage molecule. * Every cell makes its on ATP, depending on how active it is and its job. * ATP is constantly made and used. 40 kg is made in a 24hr period. Structure Organic base - adenine Pentose sugar - ribose 3 Phosphate groups - inorganic phosphates which are joined by high energy bonds. ATP is a nucleotide and because of its structure, is water soluble and is easily transported around the cell. To release the energy in ATP it is hydrolysed. When water is added, a phosphate group is broken off and energy is released. An enzyme called ATPase catalyses this reaction. When phosphate 1 is removed, a total of 30.6 kJ mol-1

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Global Warming

> Global Warming can be defined as the term used to refer to the fact that the average temperature around the earth is increasing. > Global Warming is caused by many different factors which are mostly as a result of human activities such as the burning of fossil fuels like coal, oil and wood which produce carbon dioxide > The excess Carbon Dioxide that is released in the atmosphere is also contributed by the emission of fumes by factories and motor vehicles. The extra carbon dioxide therefore creates a 'blanket' around the earth resulting in the rapid increase of temperature > Over the past century there has been a marked increase in the concentration of he Greenhouse gases. Greenhouse Gases include carbon dioxide, water vapour, methane, nitrous oxide and ozone. > The Green house gases are also play a huge role in global warming as these gases trap the heat that would otherwise escape to into space. This is called the greenhouse effect > Deforestation is also another cause of global warming because when the excess amount of trees are cut down and not replanted, there becomes an increase in Carbon Dioxide concentration in the atmosphere as there are no trees to use it for respiration. This Carbon dioxide therefore plays a role in global warming as it begins to trap heat on the earth's surface. Consequences of Global Warming > Global warming results in many changes in

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Why is pyramid of biomass important in illustration than pyramid of numbers?

Task - Providing information about biomass; two examples of studies or research into biomass. Why is pyramid of biomass important in illustration than pyramid of numbers? Information about biomass - A biomass is a measure of the amount of living material present such as the biomass of plants in a rainforest or of worms in the soil. Biomass is expressed in units such as gm-2. These units reflect both the mass and the size of the sample. Because the amount of water in living organisms is very variable, samples are often dried, in which case the term dry biomass is used. It is not essential, however, to use dry biomass. There are some circumstances where it is far more sensible and convenient to consider fresh or live biomass. Pyramids of biomass may be expressed in terms of biomass at each trophic level. Information from: http://www.tutorvista.com/content/biology/biology-iv/ecosystem/biomass-pyramid.php "Pyramid of biomass is the graphic representation of biomass present per unit area of different trophic levels, with producers at the base and top carnivores at the tip". The total amount of living or organic matter in an ecosystem at any time is called 'Biomass'. In a terrestrial ecosystem, the maximum biomass occurs in producers, and there is progressive decrease in biomass from lower to higher trophic levels. Thus, the pyramid of biomass in a terrestrial ecosystem is

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Should everyone be to taking statins to reduce the risk of cardiovascular disease

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

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The aim of this experiment is to research on the effect caffeine has on Daphnia heart rate.

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

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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

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