Digestive Enzyme Experiment - Essay Example

Digestive Enzyme Experiment 1. Short Introduction This laboratory test aims to examine which among the three (3) types of food (i.e. break, milk, and potato) contains glucose, protein, starch, and fat. For the digestive enzyme experiment, the test will seek to determine the optimum temperature in which the enzymes will work best in the human body (i.e. 5oC, 20oC, 40oC, and 60oC). Using charts and tables, this report will record and critically analyze the laboratory test results. 2. Laboratory Test Results Carbohydrates, fats and protein are all classified as macronutrients (Shetty, 2010, p. 24). Based on the summary of results presented above, only milk contains fats. Known for being non-water soluble macronutrient, fats are good “source of energy” (Driskell, 2007, p. 6; Shetty, 2010, p. 24). It can also help maintain healthy hair and skin (Chopra, 2005, p. 105). Often times, fats are composed of 3 fatty acids that are joined together by a single glycerol molecule (Driskell, 2007, p. 6). Among the common sources of polyunsaturated fatty acids include vegetable oils such as sunflower, safflower, and corn oil whereas the common sources of monounsaturated fatty acids include butter and olive oil (Shetty, 2010, pp. 29–30). A high content of saturated fatty acids can be found in meat such as pork (Shetty, 2010, p. 30). Potatoes and bread contains starch whereas milk, potato, and bread contain glucose. Carbohydrates are usually composed of “carbon, hydrogen, and oxygen” (Chopra, 2005, p. 91). As such, both glucose and starch are forms of carbohydrates which are considered as our body’s main source of energy (Shetty, 2010, p. 24). In line with this, glucose is classified under “monosaccharides” whereas starch is classified under “polysaccharides” (Shetty, 2010, p. 24; Chopra, 2005, p. 91). In other words, both glucose and starch are two different forms of carbohydrates. (See Figure I – Classes of Carbohydrates below) Figure I – Classes of Carbohydrates Source: Chopra, 2005, p. 91 Only milk contains protein. Protein is mainly responsible for the repair and renewal of our body tissues, cells and muscles (Driskell, 2007, p. 8). Basically, the structure of protein is unique in the sense that it is generally build up by 20 different kinds of amino acids that are usually connected by certain peptide bonds (Shetty, 2010, p. 24). Among the good sources of protein includes plant or animal-based foods such as chicken and beef. To increase the maximum potential of athletes, their diet should include high intake of protein and fat (Driskell, 2007, p. 10). 2.1 Digestive Enzyme Experiment Temperature Test tube Time in seconds 5 A 1513 20 C 1050 40 D 248 60 E 53 The experiment results strongly suggest that as temperature goes up from 5oC up to 20oC, 40oC, and 60oC, the time needed for diastase enzyme to react also decreases. Inside the human body, the optimum temperature for diastase enzyme would be between 36oC to 37oC. Temperature higher than 37oC would mean that the person has a fever. 3. Mechanical and Chemical Digestion of Food and the Processes of Absorption and Assimilation 3.1 Digestion of Starches in the Mouth There are two (2) main reasons why the digestion of starches starts in the mouth (i.e. salivary amylase) and eventually stops as soon as the partially digested starches could reach the stomach. First, it is important to know that digestion of food nutrients can occur using either mechanical digestion or chemical enzymes and that starch is a polysaccharide that can be digested only via chemical reactions (Eliasson, 2006, p. 475; Sullivan and Cooley, 2004, p. 45). Second, the stomach is responsible for mechanical digestion (Rechtman, 2004, p. 114). Since starch cannot be digested mechanically, it is impossible for starch to be digested in the stomach. Basically, starch is a good example of complex carbohydrates (Shetty, 2010, p. 24; Chopra, 2005, p. 91). Because of the long chains of glucose that are heavily tied up together, carbohydrates such as starch can only be broken down by enzymes such as the salivary amylase (Sullivan and Cooley, 2004, p. 45). Eventually the reaction of salivary amylase can break down starch into a much simple carbohydrates which then can be absorbed in the small intestine (Eliasson, 2006, p. 475). In general, salivary amylase is not the only enzyme that can be use to digest starch. Other enzymes such as the pancreatic amylase as well as maltase can also be used in the chemical digestion of starch (McGuire and Beerman, 2013, p. 130; Eliasson, 2006, p. 475). For instance, as soon as the pancreas releases pancreatic juice like pancreatic amylase, it can further break down the polysaccharides into disaccharide or smaller units of maltose which were not broken down by the salivary amylase (McGuire and Beerman, 2013, p. 130). Maltase, commonly found in the small intestine can break down the smaller units of maltose into glucose (Eliasson, 2006, p. 475). Glucose can be easily absorbed in the blood (Riby, Smith and Foster, 2012, p. 160). Therefore, by the time starch reaches the stomach, the entire digestion process has already ended. 3.2 Explanation behind the Diagram Demonstrating the PH Reaction of Pepsin and Trypsin In general, pH level could highly affect the activities of enzymes (Simpson, 2012, p. 200). The given graph strongly suggest that enzymes like pepsin can work best at pH 2.5 level whereas trypsin can work best at pH 6.5 level. Both pepsin and trypsin are needed in hydrolyzing or digesting protein (Gropper and Smith, 2013, p. 40; Khurana, 2008, p. 361). Assuming that the pH level would either move above or below the pH 2.5 level, pepsin will not be able to digest protein properly. The same applies to the case of trypsin. Assuming that the pH level would either move above or below the pH 6.5 level, trypsin will not be able to digest protein properly. 3.3 Transport of Digested Amino Acid, Monosaccharides, Fatty Acids, and Glycerol through the Small Intestine’s Microvilli and Villi 3.3.1 Amino Acid Amino acid is actually the end-product of protein digestion (Schlenker and Roth, 2011, p. 34). Before the digested amino acid can be transported through the small intestine’s microvilli and villi, digestion of protein starts in the stomach and ends in the small intestine as amino acids. In the stomach, pepsin starts digesting the proteins (Starr, Evers and Starr, 2015, p. 451). As soon as it reaches the small intestine, the intestinal and pancreatic enzymes would then complete the chemical digestion process of protein by converting the polypeptides into amino acids (Starr, Evers and Starr, 2015, p. 451). Eventually, amino acid would then be transported first into the small intestine’s microvilli followed by the small intestine’s villi (Starr, Evers and Starr, 2015, p. 451). 3.3.2 Monosaccharides Monosaccharides are the end-product of carbohydrate digestion (Schlenker and Roth, 2011, p. 34). Before the digested monosaccharides can be transported through the small intestine’s microvilli and villi, digestion of carbohydrates starts with the mouth via salivary amylase followed by the intestinal and pancreatic enzymes found in the small intestine. Eventually, the monosaccharide would then be transported into the small intestine’s microvilli and villi respectively (Starr, Evers and Starr, 2015, p. 451). 3.3.3 Fatty Acids Fatty acids are actually the end-product of fat digestion (Schlenker and Roth, 2011, p. 34). Before the digested fatty acids can be transported through the small intestine’s microvilli and villi, digestion of fat starts with the intestinal and pancreatic enzymes together with the help of the bile before the fatty acids can be transported into the small intestine’s microvilli and villi respectively (Starr, Evers and Starr, 2015, p. 451). 3.3.4 Glycerol Glycerol is the end-product of fat digestion (Schlenker and Roth, 2011, p. 34). Similar to fatty acids, digestion of glycerol starts with the intestinal and pancreatic enzymes together with the help of the bile before the fatty acids can be transported into the small intestine’s microvilli and villi respectively (Starr, Evers and Starr, 2015, p. 451). 3.4 Blood Sugar Level Increased at Its Peak 10 Minutes after Eating Snickers Bar One of the main reason why blood sugar level could immediately increase at its peak right after eating a Snickers bar is because this type of food is rich carbohydrates and does not contain much dietary fibre which could have at least modulate the increase in blood glucose level (Anderson, Root and Garnez, 2015, p. 112). Another reason for this is because of the fact that the process of carbohydrates digestion starts in the mouth via salivary amylase which is not common when digesting either fat or proteins (Starr, Evers and Starr, 2015, p. 451). This explains why the glycemic index of a Snickers bar is as high as 51 (Anderson, Root and Garnez, 2015, p. 112). The reason why the blood sugar would eventually start to decrease after 10 minutes from the time the Snickers bar was ingested is because immediately after detecting a high glucose level in the blood, the pancreas would automatically response by secreting some insulin (Timiras, 2007, pp. 221–222). Basically, it is the insulin found in the human body which is responsible in moving the glucose found in the blood into the cells (Timiras, 2007, pp. 221–222). 3.5 Research Assistant: Effective Laxative Should Not Irritate Intestinal Mucosa and Should Provide Bulk There are so many reasons why an effective laxative should be one that will not irritate the intestinal mucosa and should at least be able to form bulk. First of all, one of the main reasons why it should not irritate the intestinal mucosa is because of the fact that the process of irritating the intestinal mucosa can lead to diarrhoea, electrolyte imbalance, and dehydration (Sommers and Fannin, 2015, p. 184; Spratto and Woods, 2011, p. 1993). Furthermore, the mere act of irritating the intestinal mucosa could result to rectal bleeding (Sommers and Fannin, 2015, p. 184). For example, the use of stimulate laxative can trigger alteration in the secretion of electrolytes (Spratto and Woods, 2011, p. 1993). Effective laxative should form bulk as it absorbs more water which can effectively soften stools and eventually stimulate the intestine to trigger bowel movement (Spratto and Woods, 2011, p. 1993). By softening and breaking down dry or hard stools, the use of laxatives that forms bulk (i.e. bran or psyllium) can either stimulate peristalsis or can serve as an emollient gel which could help promote safe and easy passage of stool (without causing the end-user to have diarrhoea) (Spratto and Woods, 2011, p. 1993). Basically, high intake of dietary fibre is necessary to lessen intraluminal pressure that can cause colonic diverticula (Hughes, 2005, p. 193). It means that one of the most obvious problems with using laxative that does not provide bulk is that it increases the end-users’ risk of experiencing diverticulosis. 3.6 Nutrients Acted On the Site of Action and End Products such as Chymotrypsin, Lactase, Lipase, and Bile Chymotrypsin is actually an enzyme that acts on proteins in the small intestine to produce end-product called “peptides” (Textbook Equity, 2014, p. 1001). Lactase is an enzyme that acts on lactose or milk sugar in stomach to form glucose and galactose (Shetty, Nandini and Pai, 2008, p. 24). Both lipase and bile work hand in hand in order to digest lipids (Textbook Equity, 2014, p. 1002). The site of action of both lipase and bile is in the small intestine. Basically, the end product of lipase is fatty acids and glycerides whereas the end product of bile is the small lipid globules (Textbook Equity, 2014, p. 1002). Enzyme Nutrients Acted On Site of Action End Product Chymotrypsin Proteins Small Intestine Peptides Lactase Carbohydrates (i.e. Lactose or milk sugar) Stomach Glucose + Galactose Lipase Lipids Small Intestine Fatty Acids + Glycerides Bile Lipids (i.e. triglicerides) Small Intestine Small Lipid Globules Source: Textbook Equity, 2014, p. 1002; Shetty, Nandini and Pai, 2008, p. 24 4. Conclusion Carbohydrates, fats and protein are all macronutrients needed by the human body. Although fats can be a source of energy, carbohydrates are considered as the main source of energy. Proteins are also important when it comes to repairing tissues or cells. Digestion of these macronutrients varies from one another. Fat and protein digestion starts in the stomach whereas digestion of carbohydrates starts in the mouth. Different pancreatic enzymes are mostly responsible in digesting these macronutrients via chemical reaction. References Anderson, J., Root, M. and Garnez, S. (2015). Human Nutrition. Burlington, MA: Jones & Bartlett Learning. Chopra, P. (2005). Food & Nutrition Education. New Delhi: S.B. Nangia. Driskell, J. (2007). Sports Nutrition: Fats and Proteins. Boca Raton, FL: CRC Press. Eliasson, A. (2006). Carbohydrates in Food. 2nd Edition. Boca Raton, FL: CRC Press. Gropper, S. and Smith, J. (2013). Advanced Nutrition and Human Metabolism. 6th Edition. Belmont, CA: Wadsworth Cengage Learning. Hughes, W. (2005). Clinical Pharmacy. South Yarra: MacMillan Publishers. Khurana, I. (2008). Essentials of Medical Physiology. Noida, UP: Elsevier. McGuire, M. and Beerman, K. (2013). Nutritional Sciences: From Fundamentals to Food. 3rd Edition. Belmont, CA: Wadsworth Cengage Learning. Rechtman, M. (2004). CliffsStudy Solver Biology. Haboken, NJ: Wiley Publishing Inc. Riby, L., Smith, M. and Foster, J. (2012). Nutrition and Mental Performance: A Lifespan Perspective. Hampshire: Palgrave Macmillan. Schlenker, E. and Roth, S. (2011). Williams' Essentials of Nutrition and Diet Therapy - Revised Reprint. Missouri: Elsevier Mosby. Shetty, B., Nandini, M. and Pai, V. (2008). Biochemistry for Physiotherapy and Allied Health Sciences Students. New Delhi: Jaypee Brothers Medical Publishers Ltd. Shetty, P. (2010). Nutrition, Immunity and Infection. Oxfordshire: CABI International. Simpson, B. (2012). Food Biochemistry and Food Processing. 2nd Edition. Oxford: John Wiley & Sons, Inc. Sommers, M. and Fannin, E. (2015). Diseases and Disorders: A Nursing Therapeutics Manual. Philadelphia, PA: F.A. Davis Company. Spratto, G. and Woods, A. (2011). Delmar Nurse’s Drug Handbook 2011: Special 20 Year Anniversary. New York: Delmar Cengage Learning. Starr, C., Evers, C. and Starr, L. (2015). Biology Today and Tomorrow with Physiology. 5th Edition. Boston, MA: Cengage Learning. Sullivan, R. and Cooley, D. (2004). Digestion and Nutrition. New York: Infobase Publishing. Textbook Equity. (2014). College Biology Volume 3 of 3. Timiras, P. (2007). Physiological Basis of Aging and Geriatrics. 4h Edition. Boca Raton, FL: CRC Press. Read More