...Introduction & Hypothesis: Enzymes are important for every living organism, because they are the reason that reactions occur. Although most reactions would take place without enzymes, enzymes allow these chemical reactions to happen at a much faster rate, therefore making cells more efficient (Reece, 2011). Enzymes are catalysts, and almost always proteins, that speed up the rates of reactions by lowering the activation energy without being consumed in the reaction (Helms, 1998). Throughout this experiment, four procedures will be performed to indicate the factors that alter the functioning of enzymes, and the importance that these factors are to be in correct levels in order for a cell to function properly. Proteins are macromolecules with unique polypeptide chains that make up their structure (Reece, 2011). The functions of proteins are dependent on their structure, and since enzymes are almost always proteins, the structure of the enzyme is very important for the enzyme to function. However, there are factors that can disrupt the structures of enzymes. These can be environmental factors such as temperature and pH, or they can be concentration changes, such as an increase or decrease in enzyme or substrate concentration (Eed, 2013). Temperature is an environmental factor that can alter enzyme activity (Reece, 2011). An increase in the kinetic energy of a solution results in an increase in temperature (Reece, 2011). As the temperature increases, the molecules in the...
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...The Effects of Peroxidase on Enzyme Activity Gianna Crowe Bio Lab 117 October 16th, 2014 Most enzymes are proteins that speed up reactions and are characterized as catalysts. Enzymes work in such a way that when the right chemicals of a molecule are present for the enzyme, it will fully fit the shape. The part of the particular shape is called the active site of the enzyme, since this is where the reaction occurs. The molecule that the enzyme works on is called the substrate. An enzyme reaction includes a substrate (substance) that is converted to another product. The unique shape of the active site of the enzyme allows it to bind with only certain kinds of molecules, which is the substrate of the enzyme (Strobl 2014). A substrate binds to the active site of the enzyme to form a enzyme-substrate complex for a very short time, this then becomes part of a new formation and a new product of a specific reaction is formed then released freeing the active site, allowing the enzyme to repeatedly bind another substrate. Enzymes are produced by all living things, and are a necessity to life. They are responsible for constructing, synthesizing, carrying, dispensing, delivering, and eliminating the many chemicals associated in living organisms (Colpa 2014). An example for how enzymes work in living organisms would be the process of food digestion, enzymes work to break down food and speed up the digestion process. Factors that affect enzyme activity deal with environmental conditions...
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...Introduction Enzymes are protein molecules that catalyze chemical reactions in all living organisms. Enzymes allow living organisms to carry out complex chemical activities at low temperatures, but can’t cause a reaction that hasn’t occurred in their absence. Also, enzymes are thought to speed up reactions by bringing reacting molecules together to increase the chances that a reaction will occur (Worthington Biomedical Corporation, 2015). Each enzyme has a specific active site where the substrates attach. Many factors can affect enzyme activity such as temperature, pH, and the presence of inhibitors (John W. Kimball, 2014). The purpose of this lab was to examine factors affecting the enzyme function of peroxidase. In the 19th century French chemist Louis Jacques discovered catalysts. Catalysts are substances that enable a chemical reaction without participating in it, which led to specifically peroxidases. The structure of peroxidase is a very large enzymatic protein, and has complex molecules with complicated shapes involving multiple folding’s. The activity of peroxidase is dependent on pH. It exhibits maximum activity at a pH between 6.5 and 7.0. The activity of the enzyme is reduced when pH levels are increased. Peroxidase promotes the oxidation of various compounds naturally of peroxides, where hydrogen peroxide is reduced to form water (Wikimedia Foundation, 2015). Also peroxidases break compounds down into harmless substances by adding donor molecules. During this lab...
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...Ybor City Campus 1025C Laboratory Exercise 3: Characteristics of Enzymes Introduction What are Enzymes? Enzymes are very large and complex proteins that that function as catalysts. They are synthesized by the cell to perform very specific functions. Each type of enzyme has a very specific shape (conformation) which provides its specific function. The shape of an enzyme molecule is determined and maintained by many weak intermolecular interactions between many different parts of the molecule. A catalyst is a material that donates energy to reactants in order to reduce their activation energy. In other words, they allow reactions to occur with less energy input (i.e. more quickly or at lower temperatures). The very specific shape of enzymes allows them to “fit” into a reaction and reduce the energy necessary for the reaction to occur. If their shape is changed, their ability to function as a catalyst is reduced or eliminated. As biological catalysts, enzymes are important because they speed up the rate of the reaction they catalyze that would otherwise be too slow to support life. Factors Affecting Enzyme Activity The rate at which an enzyme works is influenced by several factors including temperature and pH. Enzymes are most effective as catalysts under optimum physical and chemical conditions; as conditions change away from optimum, enzyme activity decreases (Figure 1.). Changes in various environmental factors, such as temperature or pH, may affect proteins by altering their...
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...Effect of Temperature on Rate of Reaction of Catalase Abstract Properties of Enzymes focused on the variations of reaction rates amongst enzymes subjected to various circumstances such as temperature, pH levels, different concentrations of substrate, salt concentrations, Metal Copper Sulfate and lastly, the presence of an Enzyme Inhibitor. The assigned section of this laboratory for our efforts was the effect of temperature variations on enzyme reactions. To perform the experiment, we used a spectrophotometer to monitor the baseline catalase activity when they are placed in these two temperatures. In this way, absorbance can be measured over time to monitor catalase activity of the main baseline reaction. Our results showed that temperatures at higher degrees led to being inactive, whereas those at lower degrees lowered the reaction time. This comes to show that each enzyme can have a different optimal temperature and this experiment helped us to understand how reaction rate can be affected by temperature change. Introduction Thousands of complex biological processes are constantly taking place within our bodies. We require material transport, energy synthesis, and the manufacturing of various proteins, hormones, and other molecules (Source 1). Almost all of these everyday processes rely on the function of enzymes to take place. Enzymes are specifically grouped according to their function, and this information can often provide us with clues regarding what type of reaction...
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...The Effects of Temperature, pH, Enzyme Concentration , and Substrate Concentration on Catecholase Introduction Enzymes are biological proteins that speed up the reaction rate of a chemical reaction. They work in the human body by lowering activation energy making certain that reactions will initiate. For every action, there is an equal and opposite reaction. In this case, factors that influence the activity of an enzyme are called modulators. If modulators activate enzymes the reaction rate catalyzed will significantly increase, but if the modulator inactivates enzymes the reaction rate catalyzed will significantly decreased (Silverthorn, 2004). The potentially disastrous influence of temperature, pH, enzyme concentration, and substrate concentration on enzymes and other proteins is one reason why these modulators are very strictly regulated by the body (Silverthorn, 2004). Temperature, a measure of the intensity of heat, is an important factor in the activity of enzymes. The velocity of an enzymatic reaction is influenced by temperature. This is because substrates collide with active sites frequently in the presence of rapidly moving molecules. In addition, although these molecules do move rapidly the speed of the reaction drops sharply. In short, thermal agitation causes protein molecules (enzymes) to denature ( breakdown of protein structures). All enzymes have an optimal temperature at which reaction rates go fastest without denaturing the enzyme (Campbell and Reece, 2002)...
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...Title: Enzyme Introduction The main reason for conducting this experiment is to establish the various factors that affect enzymes and reaction rates. Various experiments have been conducted to help gain a wide range of the factors that affect enzyme controlled reactions. Enzymes are affected by very many factors. It was the main aim of this experiment to establish these factors and the manner in which they affect them. This experiment also seeks to establish the manner in which some enzymes like Catalase affect the rates of reactions (Cohnheim 2009). Methods To establish the factors that affect enzymes, the procedures for the experiments to be carried out had to be almost perfect. For this reason the apparatus to be used had to be cleaned thoroughly just before commencing the experiment. To avoid differentiated results, similar kinds of apparatus were used all through the experiment. In this case glass test tubes were used. Also measuring apparatuses used were of the same size and volume. In this case four experiments were carried out. The first experiment is to establish the manner in which the enzyme Catalase affects reaction rates. The procedure of this experiment is as follows; using a pencil, label tree test tubes as test tube 1, 2 & 3. On these test tubes, label two marks using the pencil. These are at the 1cm mark and at the 5 cm mark. For the first test tube, pour in Catalase enzyme up to the first mark and add Hydrogen Peroxide up to the...
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...OF ENZYMES Enzymes are extremely important and without them, the reactions in living organisms would be so slow they would hardly proceed at all. They enable metabolic reactions to proceed rapidly at low temperatures, and as well as speeding up reactions they also control them. There are two main groups of enzymes: intracellular and extracellular. INTRACELLULAR: Occur inside cells where they speed up and control metabolism. EXTRACELLULAR: Produced by cells but achieve their effects outside the cell – includes digestive enzymes that break down food in the gut. Each enzyme is usually specific to particular reactions, and are pH sensitive, with every enzyme having its own range of pH in which it functions best. They are not destroyed by the reactions which they catalyse, meaning they can repeat a reaction over and over. (McMonagle,2015) In an enzyme controlled reaction, the substrate molecules bind with the enzyme to form an enzyme-substrate complex. The reaction then takes place and the product leaves the enzyme. As mentioned above, the enzyme (unchanged by reaction) can then be used again. Below is the equation, with the double arrow meaning that the reaction can go either way, depending on the amount of substrates and products – this ensures a equilibrium, meaning the enzyme will switch if there is an abundance of product and not enough substrates, and vice versa. (Advanced Biology, pg124, 2000) ENZYME + SUBSTRATE ENZYME-SUBSTRATE...
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...In lab 7, Factors affecting Enzyme Activity, there are two parts; Effects of concentration on enzyme activity and effects of temperature on enzyme activity. In the first lab with concentration the materials needed to preform this experiment will be a LabQuest, Vernier O2 Gas Sensor, Nalgene bottle, enzyme suspension, 3.0% H2O2 , stop watch, goggles, three test tubes and dH2O and a 10 ml graduated cylinder.The first step in the procedure is to obtain three test tubes and label them 1, 2, and 3. With a graduated cylinder, fill the three tubes with 5 ml of 3.0% H2O2 and 5 ml of water. Add five drops of enzyme suspension to test tube labeled 1. Wait thirty seconds and pour solution into a Nalgene bottle. Place the O2 gas sensor into the bottle...
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...designed to investigate the effect that increasing temperature has on the enzyme catalase and its reactivity to the substrate, hydrogen peroxide. Enzymes are biological catalysts, which allow chemical reactions to occur under cellular conditions (PennState University, 2017). Cells contain thousands of different enzymes, and their activities determine which chemical reactions actually take place within the cell. Cooper G.M. (2000) stated that without enzymatic catalysts, most chemical reactions are so slow that they would not occur, as enzymes accelerate the rates of such reactions by over a million-fold. Freeman, S. (2006) illustrated that chemical reactions require an input of energy to begin called the activation energy....
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...Introduction Enzymes are biological catalysts. Catalysts are substances that increase the rate of chemical reactions without being used up themselves. Enzymes are also proteins. They all have different and complex shapes that allow smaller molecules to fit into them. The place where these substrate molecules fit is called the active site. The shape of an enzyme can change; its active site may no longer work. It is said the enzyme is denatured. They can be denatured by high temperatures or extremes of pH. Like all other proteins, enzymes are made of amino acids. Each enzyme is made of between 100 to 1 million amino acids placed like pearls on a string. Each amino acid is bonded to the next by chemical bonds. Some enzymes can be made from 20 different kinds of amino acids. No two enzymes are alike. Each enzyme has its own unique sequence of amino acids, which is determined by the genes in the cells. Enzymes consist of millions of amino acids placed one after the other, however, do not look like a long string of amino acids. In most enzymes the string is coiled and folded thousands of times to form a highly complex three-dimensional structure. It is the chemical interactions between the amino acids that force the enzymes into their three-dimensional structure, which is held together by the many different links between the different amino acids. Each enzyme has its own unique three-dimensional structure that determines the function of the enzyme. The three-dimensional structure...
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...The premise of this lab is to measure our enzymatic activity of Alkaline phosphatase, we began measuring our activity by applying different substrate concentration of p-nitrophenyl phosphate in relationship to absorbance over the span of 70 seconds, the data obtained in table 5.1, the different substrate concentration 0.9mM, 0.675mM, 0.45mM, 0.225mM, 0.09mM, 0.045mM, 0.0225mM. keeping our enzyme constant at 100μL, what we concluded is a significant decrease on the absorbance as we decrease the substrate concentration, for example our initial reading of absorbance at 0.09mM concentration was 0.558, the same reading at 0.0225mM was significantly lower (0.176) thus indicating that substrate concentration does influence absorbance if the enzyme concentration remains constant....
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...Factors Affecting Enzyme Activity Analysis of Enzyme Activity: Catalase and Tyrosinase Introduction to Neurotransmitters: Acetylcholinesterase Abstract: A series of three labs were combined to observe the effects of some common biological enzymes: Catalase, Tyrosinase, and Acetylcholinesterase (AChE). Enzymes are catalytic proteins, that when present in a chemical reaction, are able to lower the action potential needed to create the reaction without being destroyed or altered themselves in the process. In Part A, my hypothesis stated that when Catalase is combined with H2O2 the rate of conversion to water and oxygen gas should double when 5-10 drops of enzyme is added and quadruple when 10-20 drops are added. In Part B, my hypothesis stated that increases in enzyme concentration or buffer pH the substrate of the final product will yield increased substrate, also, if the substrate concentration is increased then the enzyme will be less diluted, the buffer pH will increase, or there will be a temperature increase. In Part C, my hypothesis stated that tacrine will have an inhibitory effect on AChE, and that those effects will increase as the level of concentration increases. In all three labs I postulated that increases in temperature and concentration levels and would increase the rates and decrease time to form chemical reactions. We setup each lab with a series of increased concentrations and a control trial using DiH2O. We observed the results using the...
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...The purpose of the enzyme lab conducted was to observe the chemical composition of cells. In order to do so we tested for the presence of organic molecules. Molecules are what forms when atoms bond together. Organic molecules of cells include proteins, carbohydrates, and lipids, which are composed of smaller molecules known as monomers and polymers. Polymers are joined monomers. A chemical reaction links monomers together occurs and releases a water molecule, this is called dehydration synthesis. Hydrolysis separates polymers into monomers by using water to break bonds. Organic catalysts called enzymes are proteins that increase the speed of a chemical reaction. In the lab we used Biuret reagent to test for proteins, iodine solution to test for starch, paper to test for lipids. In the first lab, we tested for the presence of proteins in samples by using blue solution called Biuret reagent, which changes to purple when a protein is present and pinkish-purple for peptides. First test tubes were marked at 1cm and then filled to the mark with water, albumin, pepsin, and starch. Next, five drops of Biuret reagent was added to the sample, covered with Parafilm, and swirled to mix. The water remained clear, indicating the sample lacked the presence of proteins, and thus was our negative control. The albumin sample observed changed to an orange-purple color, indicating the presence of protein. The peptin sample changed to a pink-purple hue, testing positive for presence of peptides...
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...Chapter 3 Enzymes Learning Outcomes Candidates should be able to: (a) explain that enzymes are globular proteins that catalyse metabolic reactions; (b) explain the mode of action of enzymes in terms of an active site, enzyme/substrate complex, lowering of activation energy and enzyme specificity; (c) [PA] follow the progress of an enzyme-catalysed reaction by measuring rates of formation of products (for example, using catalase) or rates of disappearance of substrate (for example, using amylase); (d) [PA] investigate and explain the effects of temperature, pH, enzyme concentration and substrate concentration on the rate of enzymecatalysed reactions; (e) explain the effects of competitive and non-competitive inhibitors on the rate of enzyme activity; (f) use the knowledge gained in this section in new situations or to solve related problems. Enzymes are globular protein which act as catalysts • Enzymes are protein molecules defined as biological catalysts which speed up a chemical reaction and remain unchanged at the end of reaction. • Enzyme names end in –ase E.g. amylase, ATPase • Enzyme are globular proteins. Enzymes are globular protein which act as catalysts • Enzyme molecules are coiled into a precise threedimensional shape, which hydrophilic R groups (side-chains) on the outside of the molecule ensuring that they are soluble. Enzymes are globular protein which act as catalysts • Enzyme molecules have active site. • The active site of an enzyme is a region...
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