Investigating the breakdown of hydrogen peroxide using celery tissue to supply the enzyme catalyst
Investigating the breakdown of hydrogen peroxide using celery tissue to supply the enzyme catalyst Variables * Amount of celery * Concentration of celery, more or less watered down. * Concentration of Hydrogen Peroxide (H202) * The amount of H202 * The temperature of H202 I am going to vary the concentration of the hydrogen peroxide. I think that varying the concentration of the liquid will be the best experiment to do and will hopefully give a strong set of results, which will enable me to obtain clear conclusions. Prediction The rate of an enzyme- controlled reaction depends on the temperature, pH, and concentrations of the enzyme and its substrate. The more enzyme molecules produced by a cell, the faster the reaction will proceed. Similarly, an increase in the substrate concentration will speed up the reaction if there are enough enzymes molecules to cope with the additional substrate. Therefore by diluting the hydrogen peroxide with water, this will decrease the rate of decomposition of the H202, and the less gas will be given off. The enzyme in the experiment is catalase. Hydrogen peroxide is poisonous and the catalase works to render the hydrogen peroxide harmless by breaking it down to water and oxygen. If the concentration of H202 is less, then there is more water present, and there are less hydrogen peroxide molecules, so there is less for the catalase to
Uses of enzymes In industry and Medicine
Uses of enzymes In industry and Medicine Enzymes are biological catalysts, which control the biochemical reactions in a cell. The function of each enzyme is determined by its complex structure. The active site is where the reactions take place and the rest of the enzyme acts as scaffolding. All enzymes are proteins. They are made from amino acids. These are made of five elements - carbon, hydrogen, oxygen, nitrogen and sulphur. The general structure of an amino acid molecule is shown below. Amino acids are joined by condensation and a water molecule is removed. The bond formed as a result between the two amino acids is called a peptide bond. When two amino acids join together a dipeptide is formed. Three amino acids form a tripeptide. Many amino acids form a polypeptide. In a protein the polypeptide chain may be hundreds of amino acids long. Amino acid polymerisation to form polypeptides is part of protein synthesis. It takes place in ribosomes. The protein structure is broken down into four levels; these are the primary structure, the secondary structure, the tertiary structure and the quaternary structure. The primary structure is a sequence of amino acids in a polypeptide chain. It determines the rest of the protein structure. Finding the primary structure of a protein is called protein sequencing. The secondary structure is held together by hydrogen bonds
edexcel unit 1 biology
Unit One - Lifestyle, Health and Risk Biological Molecules A macromolecule is a giant molecule made from many repeating units. In Biology, polymers are long chains of biological molecules made up of units that can be pulled apart to form more simple substances e.g. starch can be broken down into glucose monomers. A polymer is formed when monomers link together. In order to do this a simple reaction occurs to bond the monomers together. This is called a condensation reaction and is where a molecule of water is removed. Not all polymers link this way, but starch and proteins do. Carbohydrates Carbohydrates are a very large group of biological molecules, with diverse functions. They are compounds containing carbon, hydrogen and oxygen. They are the most abundant organic compounds found in nature being produced by green plants and photosynthetic bacteria: Solar energy 6CO2 + 6H2O › C6H12O6 + 6O2 The small, simple ones are metabolic i.e. part of the cell's reactions e.g. glucose, fructose, maltose. The larger ones are used for storage (of glucose) e.g. starch in plants and glycogen in animals. They are also structural e.g. cellulose in plant cell walls. Monosaccharides: These are the simplest of the sugars, containing only one unit or monomer. They are sweet, soluble crystalline molecules of low molecular mass. Each contains an aldehyde (- CHO) or a ketone (-
Respiration Assessment
Cell Biology Respiration Assessment Cell Biology Respiration Assessment An Overview The anaerobic respiration of glucose has four distinct stages . Glycolysis 2. Pyruvate oxidation (the "link" reaction) 3. The Krebs Cycle 4. The Electron transport chain Glycolysis A glucose molecule is converted into 2 molecules of pyruvate, a 3-carbon compound. It does not require oxygen and produces 2 molecules of ATP. Glycolysis takes place in the cytosol, the fluid part of the cytoplasm. Overall, for each molecule of glucose, glycolysis produces: * 2 molecules of ATP (4 are created but 2 are used up in glycolysis) * 2 molecules of NADH (reduced coenzyme which later feeds electrons into the electron transport chain) * 2 molecules of pyruvate (which enters the "link" reaction if oxygen is available) Pyruvate Oxidation This is the reaction, which links glycolysis with the Krebs cycle. In the presence of oxygen, pyruvate moves from the cytosol to the mitochondrial matrix where it is oxidised into acetate (a 2c molecule), producing carbon dioxide as a by-product. This reaction also produces 2 molecules of NADH. The acetate is picked up by a carrier molecule coenzyme A, and acetyl coenzyme A is formed. This reaction is called oxidative decarboxylation. The Krebs cycle The main purpose if the Krebs cycle is to produce a continuous supply of electrons to feed into the electron
To determine if the rate of reaction of free enzymes is higher that the rate of reaction in immobilised enzymes in different pH concentrations of solution.
AS Level Human Biology Investigation into the effects of pH on free and immobilised amylase By: Laura Carolan-Munslow Aim: To determine if the rate of reaction of free enzymes is higher that the rate of reaction in immobilised enzymes in different pH concentrations of solution. Introduction: Enzymes are biological catalysts that help biological reactions, which normally occur very slowly at biological temperatures, to occur faster. Enzymes do this by lowering the activation energy (the energy required to get the reaction started, and break some bonds initially). By lowering the activation energy, the reactions can occur much faster. Most enzymes are globular proteins, (though some are RNA enzymes). Protein enzymes have a 3D formation, which has to remain intact for the enzyme to function correctly. If this 3D shape is destroyed, or even altered, the enzyme cannot function. When this happens the enzyme is said to be denatured. An enzyme can be denatured in various ways; the main factors that affect the activity of the enzyme are pH, temperature, and substrate concentration. If the pH is higher or lower than the optimum level, then the enzyme will denature. If the temperature is too high, the bonds of the 3D shape will break, and thus the enzyme will denature. Every enzyme has an optimum pH, (the pH at which the enzyme will function best) at this pH the
What is the Effect Of Changing Temperature on the Activity of the Enzyme Pectinase?
What is the Effect Of Changing Temperature on the Activity of the Enzyme Pectinase? Planning Hypothesis When I increase the temperature of the pectinase, its activity will also increase, which will be shown by the yield of juice. Due to the molecules warming up and then moving around more, the frequency of collisions between particles will increase. However this will be restricted, , after its peak of 40ºC, the Pectinase would start to denature and the rate of juice production will fall drastically. By 80ºC I predict the enzyme will be completely denatured, which will be shown by a low yield of juice. Biological catalysts called enzymes control the metabolic reactions. Pectinase is the enzyme in my investigation. It is used as an industrial enzyme for the production of fruit juice, sometimes along with cellulase. It works by hydrolyzing the pectin's which hold the cells of the pulp together, making the cells fall apart and release the juice from inside the vacuole. During the fermentation of the fruit juice, Pectinase removes the cloudiness of the solution caused by the presence of pectin. Apparatus - 500g of apple pulp. The pulp will be prepared before the experiment with the use of a potato masher. - 2% pectinase solution - 2 conical flasks - Weighing scales - 2 ice cream tubs. I will use an ice cream tub for my water bath and keep refilling it with water of
cell and organ structures in humans
The basic component of a cell is: * Plasma membrane- This controls the movement of substances into and out of the cell. Its complex structure with a phospholipid bi-layer and many different associated protein molecules. Some of these act as pathways into and out of the cell. * Nucleus- This is the control centre of the cell and contains the genetic material. * Endoplasmic reticulum- There is two different types of endoplasmic reticulum, rough and smooth. Rough is associated with ribosomes. These ribosomes make proteins for export to the rest of the organism. Where as smooth do not have ribosomes. One of its functions is the production of lipids. * Golgi- The Golgi apparatus is rather like a post office. It may be thought of as attaching chemical labels to proteins and sending them to other parts of the cell or out of the cell to another part of the organism. It also helps to export carbohydrates and lipids from the cell. * Mitochondrion- Mitochondria are large organelles. Each one is a site of energy release by the process of respiration. The more energy a cell needs the more mitochondria it has. They are very easy to recognise by their distinctive inner membrane. * Ribosomes- These are very small organelles. They make proteins from amino acids. * Lysosome- Lysosomes are enzyme-filled sacs. They are surrounded by membranes, which prevent most of these enzymes leaking
Investigate How Enzyme Concentration Affects The Rate of Reaction
Investigate How Enzyme Concentration Affects the Rate of Reaction Null hypothesis: No matter what the concentration of the enzyme; the rate of the reaction will always be the same. Introduction: The aim for the investigation is to find out how enzyme concentration affects the rate of reaction, in this case investigating the breakdown of protein by protease enzymes. The variables that could play a part in the experiment could be the amount of the substances used (5cm), the room/test tube and translucency /substances temperature, or concentration of enzyme. The independent variable was the amount of the substance used as it is measured. The lock and key hypothesis is a simple model of how an enzyme works, the substrate fits into the active site to form a reaction intermediate. The Lock and Key Hypothesis http://www.chemsoc.org/networks/learnnet/cfb/enzymes.htm In this model of the lock and key process, the enzyme molecule changes shape as the substrate closes in. The change in shape is 'induced' by the oncoming substrate molecule. Enzymes are biological catalysts and you can lower the activation energy by using a catalyst. The Activation energy is the threshold of energy, in other words the amount of energy needed to make a chemical reaction to occur. There are 3 necessary requirements in order for a chemical reaction to take place; firstly molecules must collide to
Core Practical Mint or Garlic Toothpaste? Testing anti-bacterial properties.
Core Practical - Mint or Garlic Toothpaste? Hypothesis I think that the garlic will have higher antibacterial properties than the mint. This is because the garlic is more acidic, and therefore will be able to destroy the bacteria easier, and have a larger zone of inhibition. Variables The Independent variable in this investigation is the presence of the garlic or mint. The Dependant variable in this investigation is the zone of inhibition around the disc. This will be measured by measuring the zone around the disc, using a ruler, after the Petri dish had been left for an adequate amount of time. The control variable was the length of time that the mint or garlic had to kill the bacteria. This was controlled by everyone leaving the dishes for the same amount of time, 48 hours. Other variables includes concentration of plant material, lawn of bacteria on Petri dish, contamination of Petri dish by other microbes, and the volume of plant material on each disc. Equipment • Agar plate seeded with bacteria • Plant material (garlic cloves and mint leaves) • Pestle and mortar • 10 cm industrial methylated spirits • Pipette (sterile) • Paper discs (e.g. Whatman antibiotic assay paper discs) • Sterile Petri dish • Sterile forceps • Tape • Marker pen • Incubator set at 25 °C Method ) To make the plant extract, crush 3g of either
The enzymes will be in a substance called trypsin, and will be mixed together when at the acquired temperature with the substrate which is 2% milk. As long as the enzyme hasn't become denatured at too hotter temperature
What Are The Effects Of Temperature On Enzyme Activity? Introduction We are trying to discover what effect temperature has on enzyme activity. Hopefully my results will show me that temperature does have some effect on the activity of the enzymes and show me at what temperature enzymes become denatured. I will use 5 different temperatures from 10ºC to 50ºC which will hopefully be enough to supply me with the results I want, these may not show when enzymes become denatured but I may do 1 other temperature once to show when they become denatured . Variables I could change many variables for this experiment; I could change temperature, volume of milk or volume of enzymes, the concentration of milk or enzymes, those could all be used to show an effect on the enzyme activity, however, I am investigating the effects of temperature on enzyme activity so henceforth my variable will be temperature. Apparatus: * 2 x Test tubes, 1 for the milk and one for the trypsin. * 1 x test tube rack. * 2 x plastic syringes with measuring marks on them, one for the trypsin and one for the milk so they don't mix before you even start the experiment. * 3 x water baths, 30 ºC, 40 ºC and 50 ºC (A fifth may be needed if room temperature is below 20 ºC in your classroom.) * 1 x Ice Bath, 10 (A second may be needed if room temperature is above 20 ºC in your classroom.) * 1 x timer to time
