The effect of amylase concentration on the breakdown of starch
The effect of amylase concentration on the breakdown of starch This Essay was awarded a mark of A, so they say. Only the plan is included For this investigation I am going to investigate the effect of the concentration of an enzyme, in this case Amylase, on the time taken for the enzyme to fully breakdown the substrate, which in this case is starch. The reason why these two enzymes have to be used is because each enzyme is designed specifically to break down only one substrate as each enzyme is made of a protein that causes it to be a specific shape, in this case the enzyme Amylase can only break down starch to dextrin. I am going to do this by planning an experiment, carrying out the experiment, recording any relevant results and plotting graphs from which I will be able, hopefully to gain a strong conclusion. I will finally evaluate the whole investigation. Before the experiments start we will be given a bottle containing a 1% solution of starch and another bottle containing a 1% solution of the enzyme Amylase. From these bottles I will be able to take out as much of either solution as I wish. I cannot start he experiment until I know which factors I am going to change and which I am going to keep constant. Because the thing I am trying to test in the effect of the concentration of the enzyme, the only thing that I should be changing in each experiment is the
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
Investigate the effect of pH on Trypsin
Biology Coursework Plan Aim Investigate the effect of pH on Trypsin Prediction / hypothesis * pH will affect trypsin action * as pH increases, tryrpsin will show increasing activity up to an optimum pH * the action of the enzyme trypsin on the substrate egg albumen will be at a maximum at an optimum pH of around 7 (neutral) to 8 (slightly alkaline) see later about pH of duodenum * as pH continues above this, trypsin activity will decrease Background / Introduction Proteins are complex organic compounds consisting of amino acids joined by peptide bonds which form highly folded three dimensional or tertiary structures. The bonds that maintain the tertiary structure of the protein are a result of interactions between the R groups of the amino acids: disulphide bridges (strong covalent), hydrogen (weak) bonds, ionic or electrovalent bonds, hydrophobic interactions. Enzymes, such as trypsin, are globular proteins with a specific shaped active site into which the correct substrate can fit. trypsin protein / polypeptide peptides Trypsin is a protease enzyme: a hydrolytic or digestive protein that cleaves peptide bonds. It is produced in the pancreas in the form of trypsinogen, and is then transported to the duodenum of the small intestine, where the digestion of proteins to polypeptides and amino acids begins. The pH
biology differences in animal and plant cells
Sarah Huckerby 30059987 Di Paul Biology Group 1 Contrasting the structure of plant and animal cells Modern cell theory states that all living matter is composed of cells and they arise from other cells. They contain hereditary information of the organisms of which they are a part; the cell is the basic unit of all living matter. Cell are made up of Protoplasm, which is a granular substance resembling the white of an egg, the cell membrane, inorganic salts, carbohydrates for energy, Lipids which are fats and nitrogenous substances, amino acids which are obtained from proteins (Moth.E 2003) Organisms mostly consist of Eukaryotic cells, which contain a true nucleus and also contain other organelles which are sub-cellular, permanent structures that carry out particular functions in the cell. Plant and animals are composed of cells that have many similarities. All plant and animal cells have a nucleus surrounded by Cytoplasm bound by a cell membrane, cytoplasm is the material inside the cell but outside the nucleus, it contains different structures and substances. It is the "brain" of the cell and is contained within the nuclear membrane (which insures that the interior of the nucleus is isolated from the cells cytoplasm allowing two different environments to be maintained,)it contains pairs of chromosomes each carrying hereditary DNA (Deoxyribonucleic acid) (Toole, G & S
Cellular Respiration and the Role of Mitochondria
Cellular Respiration and the Role of Mitochondria Cellular respiration is the process of oxidising food molecules, such as glucose, to carbon dioxide and water and releasing the covalent bond energy in the form of ATP for use by all the energy-consuming activities of the cell. Mitochondria are membrane-enclosed organelles distributed through the cytosol of most eukaryotic cells. They are where cellular aerobic respiration occurs; indeed cells without mitochondria cannot respire aerobically. Cellular respiration consists of two broad phases, initially, glycolysis (the breakdown of glucose to pyruvic acid) Occurs, this is followed by the oxidation of pyruvic acid to carbon dioxide and water. In eukaryotes, glycolysis occurs in the cytosol (The fluid in which cell organelles are suspended). The remaining processes take place in the mitochondria. The first stage, glycolysis is the anaerobic catabolism of glucose, it occurs in almost all cells. The process uses glucose and co-enzyme NAD (Nicotinamide Adenine Dinucleotide), and yields 2 molecules of Pyruvic acid, as below C6H12O6 + 2NAD+ -> 2C3H4O3 + 2NADH + 2H+ The free energy stored in 2 molecules of pyruvic acid is somewhat less than that in the original glucose molecule. Some of this difference is captured in 2 molecules of ATP. The Krebs Cycle then decarboxylates the pyruvic acid resulting in a 2-carbon fragment of
The structure and function of the ileum in relation to absorption and digestion.
SUMUDU LANKATILAKE 7-FEB-03 THE STRUCTURE AND FUNCTION OF THE ILEUM IN RELATION TO ABSORPTION AND DIGESTION The ileum is the second part of the small intestine located after the duodenum. It has a vital function in digestion and has a suitable structure to accommodate for its functions. The ileum is 6 meters long and the main site foe the absorption of the soluble products of digestion. The ileum is efficient at this for the following reasons: * It is fairly long and presents a large absorbing suface to the digested food. * Its internal surface is greatly increased by circular folds bearing thousands of projections called villi. These villi are about 0.56mm long and may be finger like or flattened in shape. * The lining epithelium is very thin and the fluids can pass rapidly through it. The outer membrane of each epithelial cell has microvilli which increase the exposed surface of the cell by 20 times. * There is a dense network of blood capillaries in each villus for quick absorption and maintainance of the concentration of the concentration gradient. * The villi possess smooth muscle fibres that contract and relax and mix the food up and bring it into contact with the epithelial cells of the absorptive surface. * Each villus has a lacteal for the absorption of fatty acids and glycerol, most of which combine to form fats. The ileum is made up of 4 layers:
Effect of temperature on the enzyme pectinase in fruit juice production.
Effect of temperature on the enzyme pectinase in fruit juice production AIM: To investigate the effect of temperature on the work of the enzyme pectinase in fruit juice production. INTRODUCTION It is stated that temperature has an effect on Enzymes. I am going to investigate this fact using my chosen enzyme Pectinase. This enzyme is used in the fruit juice industry and I am going to use this enzyme to explore the question: How Does Temperature Affect Enzymes? BACKGROUND INFORMATION Enzymes are biological catalysts that speed up the rate of a reaction without being changed or used up in any way. They are protein molecules that are tailored to recognize and bind specific reactants and speed their conversion into products. These proteins are responsible for increasing the rates of all of the many thousand of reaction taking place inside cells. Activation energy is the energy barrier over which the molecules in a system must be raised for a reaction to take place. The use of enzymes lowers the activation energy so the reaction can proceed at a faster rate. ( GRAPH TAKEN FROM REFERENCE 7) A number of factors affect the activity of enzymes in speeding conversion of reactants to products. These factors are; . PH: Each enzyme has an optimal pH range that help maintain its normal configuration in an environment which it operates. The tertiary structure of a protein
The Effect of pH on Pectinase
The Effect of pH on Pectinase Hypothesis I plan to investigate the effects of varying pH on the enzyme 'Pectinase'. I will test the yield of apple juice from a set amount of pureed apple at different pH. I think the optimum pH for pectinase is likely to be around pH 5, an acidic pH, as many commercial pectinases are produced from fungi. Before I look at the structure of pectinase, first it would seem sensible to look at the substrate that pectinase will be working on, Pectin. Starch and Pectin are very similar molecules. Starch and Pectin are both polysaccharides. However in Pectin the repeating unit is not glucose as in starch, but galacturonic acid. Galacturonic acid is very similar to glucose, except that the carbon with CH2-OH attached in glucose is replaced by a -COOH in galacturonic acid (shown below). Bonds between carbon 1 of the first galacturonic acid and carbon 4 of the next hold pectin chains together. This sequence continues down the chain. Enzymes are biological catalysts; they alter the speed of reactions without being reactants themselves. There are two theories on how enzymes work. The first is the 'lock and key theory'. This theory suggests that substrate molecule fits perfectly into its specific enzymes active site, and only that enzyme. This can be seen below: The second theory is the 'induced fit theory'. This suggests that the active site on the
Relating the structure and function of cell organelles
Relate the structure and function of cell organelles Cells are like cities with intricate organelles 'living and working' in it. There are basically two kinds of cells, namely Prokaryotic and Eukaryotic. Both plant cells and animal cells are eukaryotic while prokaryotic cells are simplier organisms that possess non-membrane bounded organelles. In most cells they contains the following organelles which carry out unique functions and allow cells to work properly. To start off with, nucleus is a large roundish organelle enclosed by a double membrane with numerous openings, namely nuclear pores, for nuclear traffic. It contains chromosomes and one or more nucleoli. Nucleolus is a spherical site where ribosomes are formed. Chromosomes contain DNA which tends to be packed in form of chromatin. Only during interphrase (a stage before a cell divides in a cell division process), chromosomes will be unravelled for easier replication. Tiny, hollow cylinders of protein called centrioles form a network of spindle fibres in the nucleus during nuclear division to pull chromosomes apart. The inner membrane of nucleus will break down and allow chromosomes lying freely in cytoplasm. DNA contains the genetic information and control the synthesis of protein. Each cell contains millions of ribosomes. They are very tiny, non-membrane bounded organelles made of protein and RNA which consist of
structural differences between fibrous and globular proteins.
Question: Explain with examples, the structural differences between fibrous and globular proteins. A globular protein has a fixed specific sequence of amino acids that are non-repetitive while a fibrous protein has a repetitive regular sequence of amino acid. For example, haemoglobin, a globular protein is made up of 4 polypeptide chains to form a tetramer (?2?2), composed of two identical alpha-beta (??) dimers. Collagen, a fibrous protein, has a primary structure characterized by a repeating tripeptide sequence of Glycine - X - Y. (X is proline, Y is either hydroxyproline or hydroxylysine) A globular protein has a more compact structure owing to highly contorted pattern of folding, bending and twisting along polypeptide chain to give the protein a spherical 3D shape while a fibrous protein is usually formed with elongated polypeptide chains wrapped around to form multi-molecular paralleled filaments to strands. For example, haemoglobin is a tetramer made up of 4 polypeptide chains of 2? chains and 2? chains. These four subunits are packed to form an overall spherically shaped molecule. However, collagen, a fibrous protein, is formed with three polypeptide chains lie parallel and wind round one another, forming a tropocollagen. The tropocollagen molecules lie side by side and are linked to each other giving a collagen fibril. A globular protein has its length of
