The Ways in Which Organisms Use ATP

The Ways in Which Organisms Use ATP ATP, the standard abbreviation of Adenosine-5'-triphosphate is a multifunctional nucleotide used in cells as a coenzyme, and can be best summarised as the standard energy currency universal to all organisms, and as such is utilised in metabolic (and other) processes throughout the cells of organisms, and is highly adapted to its function therein due to its high instability in aqueous solutions (eg tissue fluid) due to its easily hydrolysable phosphoannhydride bonds which when broken release a proportionally huge amount of energy. ATP is required during the contraction of skeletal muscle. ADP is released by the myosin head, this allows it to change shape thereby pulling the actin filament across itself. In order to detach the myosin molecule (for it to bind to a myosin binding site further along the actin) ATP binds to the myosin head, where it is hydrolysed to release ADP (which remains on the head) and inorganic phosphate. The energy released allows the myosin head to resume its normal position prior to the release of its ADP molecule, ready to bind further along the actin filament. Furthermore, ATP is utilised elsewhere within the same process, as it is used by carrier proteins on the membrane of the sarcoplasmic reticulum as a source of energy for the active transport of Ca2+ ions into the sarcoplasmic reticulum. It is when these

  • Ranking:
  • Word count: 1102
  • Level: AS and A Level
  • Subject: Science
Access this essay

Enzymes in agriculture.

Enzymes in Industry and Medicine by David Harder Enzymes in agriculture The only major agricultural area to utilise enzymes is the feeding of monogastric animals. There are two applications, which currently utilise enzymes. Biological silage inoculants frequently contain enzymes in addition to lactic acid bacteria. The enzymes in such products partially breakdown some of the cell wall components of the plant material to be ensiled into soluble sugars. These liberated sugars are then metabolised by the natural or applied lactic acid bacteria such as Lactobacilli or Pediococci into lactic acid, which reduces the pH and so ensiles the crop. Some enzyme preparations have been reported to improve the utilisation of feeds for ruminant animals. The use of enzymes in arable agriculture especially in the processing of some major crops and in waste disposal systems is areas, which has not been fully investigated. Enzymes in baking Bread baking is one of the most common food processing techniques throughout the world although the bread products of different countries vary in their finished form. The basic component of all bread is wheat flour to which is added water, salt and yeast. Other ingredients are sometimes added such as sugar, fats and flavouring components. The main components of wheat flour are starch, protein and fibre. The wheat flour has naturally occurring enzymes

  • Ranking:
  • Word count: 1765
  • Level: AS and A Level
  • Subject: Science
Access this essay

How does the concentration of enzymes affect the breakdown of starch by a-amylase in biological washing powders?

How does the concentration of enzymes affect the breakdown of starch by ?-amylase in biological washing powders? In the cleaning business, it's important to get a maximum cleaning effect at a minimum cost. This is especially applicable to the washing of clothes (both commercially, before an item of clothing goes on the market, or at home). This means trying to wash clothes at the lowest possible temperature, to keep the amount of electricity used at a minimum, yet trying to make and maintain a low-priced washing product that cleans effectively. This is why many washing powders use enzymes: enzymes are biological catalysts that speed up the breakdown of certain substances (in this case the molecules in food stain). Enzymes have a certain optimum temperature (a temperature at which the enzymes function at its best). Optimum temperatures are different for every enzyme, but they tend to be around 45°C. This means that if enzymes are to be used in washing powders, the temperature at which the clothes are washed will have to be at the optimum temperature, in order to achieve maximum enzymatic effect. This optimum temperature, in the case of the enzymes concerned (the enzymes that break down protein, fats and starch in food stains on clothes), is lower than the normal washing temperature of clothes, 60°C, which means the use of enzymes in washing powders will reduce the washing

  • Ranking:
  • Word count: 12799
  • Level: AS and A Level
  • Subject: Science
Access this essay

Experiment investigating hydrogen bonding in different chemicals.

Tsuen Wan Public Ho Chuen Yiu Memorial College Form 6 Chemistry Practical Experiment 8: Hydrogen Bonding Date of experiment: 27-1-2011 Objective: A. To discover the existence of hydrogen bonds between ethanol molecules B. To measure the strength of hydrogen bond formed between ethanol molecules C. To investigate the formation of hydrogen bonds between molecules of ethyl ethanoate and trichloromethane D. To measure the strength of hydrogen bonds formed between molecules of ethyl ethanoate and trichloromethane Introduction: A hydrogen bond is the attractive interaction of a hydrogen atom with an electronegative atom, such as nitrogen, oxygen or fluorine, that comes from another molecule or chemical group. The hydrogen must be covalently bonded to another electronegative atom to create the bond. These bonds can occur between molecules, or within different parts of a single molecule. The hydrogen bond (5 to 30 kJ/mol) is stronger than a van der Waals interaction, but weaker than covalent or ionic bonds. This type of bond occurs in both inorganic molecules such as water and organic molecules such as DNA. Intermolecular hydrogen bonding is responsible for the high boiling point of water (100 °C) compared to the other group 16 hydrides that have no hydrogen bonds. Intramolecular hydrogen bonding is partly responsible for the secondary, tertiary, and quaternary structures

  • Ranking:
  • Word count: 2533
  • Level: AS and A Level
  • Subject: Science
Access this essay

Studying the Effect of Salt on Cress Germination

PLANNING Initial Method . Prepare 8 sterile Petri dishes with a perfectly fitting circle of cotton wool and filter paper, this will sit on top of the wool 2. A control dish must also be set up using the same steps as above 3. Weigh out 8 different salt measures, at 0.25, 0.5, 0.75, 1, 1.25, 1.5 and 1.75 4. Measure out 8, 50ml beakers of distilled water 5. Add the one measure of salt into a beaker (1 beaker for each weight) and stir until the salt is dissolved and cannot be seen 6. Add one drop of Plant nutrient growth (e.g. baby bio) to each solution 7. Add each solution into individual Petri dishes which were made up earlier on, make sure the cotton wool and filter paper are allowed a small amount of time to absorb as much water as possible before the next step 8. Add 10 Cress seeds to each of the 8 solutions and place the lid on the dish 9. Place the dishes in are area which is well lit by natural light 0. Check the dishes each day for a week and top up each dish with the same solution if it is becoming dry, add the same amount to each dish (record what you add) 1. Count and record the percentage I chose to carry out my method in this fashion as it gave me the best way to see which salt concentration had the biggest effect. I chose 8 solutions as it gives me a good range to monitor the salinity effects. The solutions are based on findings in earlier research

  • Ranking:
  • Word count: 1766
  • Level: AS and A Level
  • Subject: Science
Access this essay

descrive the biological importance of water

Making up between 70 and 95% of the mass of a cell, and covering over three quarters of the planets surface, water is one of the most important compounds on this planet. A single water molecule is made up of one oxygen atom covalently bonded to two hydrogen atoms. Covalent bonds are formed by sharing electrons between the outer shells of the oxygen and hydrogen atoms. However, what makes water so unique is the fact that it remains a liquid at room temperature. Many similar sized molecules (ammonia has a molecular mass equal to that of water-18) remain in their gaseous form at this temperature. The reasons for this unique thermal property are hydrogen bonds. The nucleus of an oxygen atom is larger and therefore contains many more protons that that of a hydrogen atom. Therefore, the electrons shared in the covalent bond between the oxygen and hydrogen atoms have a greater affinity for the oxygen atom than either hydrogen atom. This pulls the electrons closer to the oxygen atom and away from the hydrogen atoms resulting in the oxygen atom having a slightly negative charge and the hydrogen atoms developing slightly positive charges. These slight charges mean that when water molecules are close together, positively charged hydrogen atoms are attracted to the negatively charged oxygen atoms of a different water molecule. These attractions are known as hydrogen bonds and

  • Ranking:
  • Word count: 1159
  • Level: AS and A Level
  • Subject: Science
Access this essay

Problem - Maintaining the habitat of the capybara and breeding them for meat.

Problem - Maintaining the habitat of the capybara and breeding them for meat. The capybara (shown left 10) is currently classified as a common species in the 2000 IUCN Red List of threatened species. However, I have found through research that the number of capybara in the wild is declining, "Mortality from hunting is responsible for local extinctions or scarcity in many localities".1 Also this is confirmed by the statistic, "Today barely 100,000 capybaras are left in Venezuela". 2 The classification of the capybara as 'common' also means that people are unaware of the affect hunting will, and is having on the population of capybara living in the wild. The conservation of the capybara is overlooked by most people as it is considered a pest, due to its tendency to raid crops when fresh grazing is not available. The capybara has a great variety of habitats from forest and brush land to swamps, brackish mangrove areas and open savannah. The habitat needs to have all the components of water, dry ground on which to rest, grass and natural shelter1. These habitats are being destroyed by human activities, such as pollution of freshwater and the drainage of wetlands for agricultural use of the fertile soil, causing damage to the environment where the capybara seeks refuge from predators. Water is being abstracted for human usage increasing the threat to freshwater habitats.

  • Ranking:
  • Word count: 2865
  • Level: AS and A Level
  • Subject: Science
Access this essay

Electrical Hazards.

Electrical Hazards, risks of injury or death arising from exposure to electricity. Electricity is essential to daily life, providing heat and light and powering appliances in homes and factories. It must, however, be treated with great care, because the consequences of an electrical fault can be serious and sometimes fatal. Generally voltages greater than 50 volts can present a serious hazard and currents of more than about 50 milliamps flowing through the human body can lead to death by electrocution. A shock occurs when a "live" part of some device is touched, so that current passes through the body. Its severity depends on many factors, including the body's conductivity (the ease with which electricity passes through it). The conductivity is usually small, but can be increased if the body or clothing is wet. The risk of injury also increases according to the size of the voltage or current, or the duration of contact. There is a risk of electrocution (death by electric shock) if current passes across the heart. For example, if one foot is touching wet ground, the risk is greater if the arm on the opposite side touches a high-voltage source than it would be if the arm on the same side did so. Current passing into the body generates heat, which burns the tissue. Electricity can also present less direct risks. Burns are caused when hot surfaces on electrical appliances are

  • Ranking:
  • Word count: 738
  • Level: AS and A Level
  • Subject: Science
Access this essay

The cloning of Dolly.

Contents Subject Page No. Introduction 2 Definitions of Terms 3 - 4 Arguments for and against 5 - 10 What the law states on the subject 1 Case studies 2 - 14 Islamic Perspective on Cloning 5 - 17 Personal Evaluation 8 Bibliography 9 Introduction Cloning On the 23 February 1997, the world woke up to news of a new technological advance. This advance was embodied in a "little lamb" going by the name of Dolly. At first glance, one could be forgiven for wondering what was so special about this white-faced sheep. Dolly looked like hundreds of the other lambs that dot the hills and fields of Scotland; and indeed for six months this lamb had grazed quietly and unnoticed among them. Dolly appeared positively ordinary. However, Dolly, despite appearances, had a most unusual conception. She was not the end result of a fusion of sperm with egg, which had been cloned from a single cell taken from the breast tissue of an adult sheep. It was the idea that this technology could be applied to humans. The cloning of Dolly raises serious ethical questions, particularly with respect to the possible use of this technology to clone human embryos. Religious groups across the world wondered if this is a miracle was to which we can thank God for, or to ignore it as an ominous way of playing God ourselves. Ethical choices must also have to be made. The public response to

  • Ranking:
  • Word count: 4230
  • Level: AS and A Level
  • Subject: Science
Access this essay

Find the relationship between amount of fat and amount of energy produced in different foods.

July 2001 Biology Coursework Year 10 Aim Find the relationship between amount of fat and amount of energy produced in different foods. Planning I am going to ignite different foods and see how much heat energy they give out. The food that causes the biggest amount of change in temperature will have the most amount of energy. However, calculations have to be carried out to create an average energy output per gram. Variables Independent Variables: This will change from food to food, thus giving me a range of different results. In this experiment it will be type of food. Dependant Variable: This is the amount of Energy per gram which can be calculated Controlled Variables: These are the things that will keep the same, in order to sustain a fair test. These are; * Apparatus * Type of boiling tube * Distance of boiling tube from Bunsen burner * Distance of food from boiling tube * Amount of time taken to move ignited food to boiling tube Fair Test It is essential that I keep it a fair test in order to sustain accurate results for comparison at the end. To ensure a fair test, I must keep the controlled variables for every test I do. The apparatus must all be kept the same because there may be some minor differences in insulation properties, or measure of accuracy between them. If this were to happen, it would prevent me from sustaining accurate results. The same

  • Ranking:
  • Word count: 4415
  • Level: AS and A Level
  • Subject: Science
Access this essay