Enzymatic Reaction Essay, Research Paper
Situations That Govern the Pace of an Enzymatic Reaction: Enzyme Concentration, Temperature, and pHJoe SaundersBSC 1010C; T,R: 11:50-12:05Lab: T: 12:15-3:05INTRODUCTION: An enzyme is any one of many specialized organic substances, composed of polymers of amino acids that act as catalysts to regulate the speed of the many chemical reactions involved in the metabolism of living organisms. The word enzyme comes from the Greek phrase ?en yeast?. Many scientists who studied enzymes in the 1800?s studied reactions caused by yeast enzymes. There are several broad categories that enzymes are classified under, such as hydrolytic, oxidizing, and reducing, depending on the type of reaction they control. Hydrolytic enzymes accelerate reactions in which a substance is broken down into simpler compounds through reactions with water molecules. Oxidases or oxidizing enzymes are used to speed up oxidation reactions. Reducing enzymes speed up reduction reactions, removing oxygen. Other enzymes can catalyze many other reactions. When an enzyme is used in an endergonic or exergonic reaction, the enzyme accelerates the rate of the reaction. The energy activation of the reaction is decreased, speeding it up. All living cells make enzymes, but enzymes are not alive. They function by altering other molecules. Enzymes combine with the altered molecules to form a complex molecular structure in which chemical reactions take place. The enzyme molecule remains uncharged, then separates from the product of the reaction. A single enzyme can perform its entire function a million times a minute and an enzyme will speed up a chemical reaction thousands or even millions times faster than a reaction without an enzyme(Rudolph 1987). There are over 1,000 different types of enzymes in the human body. Each has its own specific job. If a person did not have any enzymes, they would not be able to digest food, breathe, see, or move. Plants use enzymes in the process photosynthesis, which is a food-making process that occurs in green plants(internet). A lot of enzymes break down complex substances into simpler ones. Others build complex compounds from simple ones. Some enzymes work outside the cell, but most are found inside. For example, the pancreas secretes the enzyme lipase, which travels to the small intestine to break down fats. Enzymes are too small to be seen with the most powerful light microscopes. Therefore, scientists know though various research techniques that enzymes occur in many different shapes and sizes. Although, enzymes of different plants and animals have different protein structures, but they function in similar ways. The structure of any particular enzyme enables it to cause certain chemical reactions in other molecules. Basically, an enzyme is like a key; if it doesn?t fit, it won?t be able to react. Although enzymes are proteins, some must be attached to certain nonprotein molecules in order to function. Many of these nonprotein molecules are metals, such as copper, iron, or magnesium. Others are organic compounds called coenzymes. If a protein has a coenzyme attached to it, the unit is called a prosthetic group. Neither the coenzyme nor the protein part of the prosthetic group can function alone. Many coenzymes consist of vitamins, especially B vitamins. If a person?s diet lacks adequate amounts of these vitamins, the enzymes cannot function properly, and various body disorders may develop.(Rudolf, 1987)Materials and Methods:The materials used in Procedure3, Enzyme Activity as a Function of Enzyme Concentration, are as follows:v Six test tubesv Test tube rackv Graduated cylinder v Hydrogen peroxidev Dropping pipettev Enzyme solutionv Grease pencilIn this experiment the subject will work with the enzyme catalase (found in ground-up cow liver), which accelerates the breakdown of hydrogen peroxide. Two ml of hydrogen peroxide was combined with enzyme catalase. This reaction created a bubble column that rose up the test tube. The tops of the bubble columns were in a relatively straight line, increasing in height with the amount of enzyme. The data was recorded.(Shuman, 1997)The Materials used in Procedure four, Effects of Temperature on Enzyme Activity, are as follows: v Substrate (hydrogen peroxide)v Test tubev Beakerv Tap waterv Enzyme solutionv Thermometer Enzyme substrate was combined with hydrogen peroxide in various test tubes. The temperature was lowered to see what the effects of the height of the bubble column. Then the data was recorded. (Shuman, 1997) The materials used in Procedure 5, Enzyme Activity as a Function of pH, are as follows:v Graduated cylinderv Buffered hydrogen peroxide solutionsv Test tubesv Enzyme solutionv Grease pencil One ml of buffered hydrogen peroxide solutions was combined with one drop of enzyme solution. After a constant period of time, the outside of each tube was marked with a grease pencil at the top of the bubble column. Then measure the height of each column and record the data. (Shuman, 1997)Results: Procedure 3 had to do with the enzyme catalase, which accelerates the breakdown of hydrogen peroxide. In each of the six test tubes, there was hydrogen peroxide. An increasing amount of enzyme solution was added to the test tubes. This caused a chemical reaction that sent a bubble column growing vertically up the test tube. The height of the bubble columns was recorded. As graph one shows, the enzyme solution was increased, the bubble column increased in size also. Shown in table one, if only on drop of enzyme solution was used, the bubble column grew only one centimeter. When two drops of the enzyme solution is used the bubble column grew 2 ? centimeters, and so on. In conclusion, the more enzyme solution added, the faster the hydrogen peroxide was broken down. Procedure four showed the effects of temperature on enzyme activity. In this activity, enzyme solution and substrate were added to separate test tubes. The test tubes were observed as the temperature was changed. As a result of the change in temperature, the bubble column in the enzyme tube increased when the temperature was rose the first three of the four temperatures used. The bubble column decreased when the last and highest temperature was read, as you can see in graph 1. Table two also shows this up and down pattern shown by the bubble column. In Procedure 5, enzyme activity was observed as a function of different pH levels. Five different pH levels were tested in this activity. As you can see in graph three, the bubble column decreased as the more basic pH level was used. Table three shows the different pH levels and the bubble column heights. Discussion: This lab can be beneficial in several ways. For one, someone can learn a lot about enzymes and enzyme activity from doing this lab. Enzymes have many uses in addition to their natural functions in the body. Manufacturers use enzymes in making a wide variety of products. For example, protein matter, such as perspiration, that causes stains. Enzymes are also used in the manufacture of antibiotics, beer, bread, cheese, coffee, vinegar vitamins, and many other products. One can use the knowledge gained from these activities for personal gain too. For example, someone that has completed this lab will know what enzymes are and how much substrate or enzyme solution the body needs for a specific function. The human body uses enzymes for everyday life and if someone knew what enzymes do your body good, that person will have an advantage on personal health.From the information in the book, the results shown the three tables and the three labs are pretty much accurate. There were only two problems that that occurred, but they seemed minor. The first problem that occurred in this lab was an inconsistency of the measurements of solutions or substrates. This had some effect in the outcome of the results, but it didn?t seem to effect them that much. The final obstacle that made a minor difference in the height of the bubble column was the moving around of the test tubes. The lab requested for the test tubes to be settling, not shaken or stirred up. Over all, the lab was very successful. The information obtained from this lab is very interesting and will be very beneficial. Enzymes are no longer a mystery. TABLE 1Data obtained on enzyme activityTable 1 compares the number of drops of catalase with the height of the bubble column.Number of drops of enzyme Height of bubble column (cm)1 1 cm2 2.5 cm3 8 cm4 9.25 cm5 10 cm6 12.5 cmTable 2Temperature versus enzyme activity. Table 2 compares temperature with the height of the bubble column (cm). Table 2 lists the different temperatures used for each reaction and the corresponding heights of the bubble columns. Temperature Height of bubble column (cm)40 2.5 cm50 3 cm65 .5 cm25 1 cmTable 3pH versus enzyme activity Table 3 compares pH with the height of the bubble column (cm). Table 3 lists different temperatures pHs used for each reaction and the corresponding heights of the bubble column. pH Height of bubble column (cm)2 3 cm4 2.5 cm7 2 cm9 1 cm11 .25 cmGraph 1Data obtained by enzyme activity Height of bubble Column (cm) Drops of enzyme solution Graph 2Effects of temperature on enzyme activity Height of bubble Columns (cm) Temperature Graph 3Enzyme activity as a function Height of bubble Column (cm) pH levelWord Cited BSC 101C Lab Manual. 1997. Lab VI, Enzymes, pp.61-64. Valencia CommunityCollege, Orlando FL.Campbell, Neil A., 1977. Biology, Fourth Edition. The Benjamin/CummingsPublishing Company, INC. pp. 90-102.Rudolph, Fredrick B., 1987. World Book Encyclopedia. World Book Inc. pp. 340-341http://www.cshl.org/books/experiments_in_mg.htmlhttp://www.molbiolcell.org/cgi/search?volume=&firstpage=&author1=&author2=&titleabstract=enzymes&fulltext=&fmonth=Jan&fyear=1992&tmonth=Mar&tyear=1999&hits=10&sendit=Search&fdatedef=1+January+1992&tdatedef=1+March+1999
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