Section 1. Introduction
“Enzymes are proteins that have catalytic functions” [1], “that speed up or slow down reactions”[2], “indispensable to maintenance and activity of life”[1]. They are each very specific, and will only work when a particular substrate fits in their active site. An active site is “a region on the surface of an enzyme where the substrate binds, and where the reaction occurs”[2].
“Lactase is an enzyme that breaks down lactose, the sugar in milk. It is produced by the cells lining of the small intestine. Most people are born producing it, but often make less of it as they age, which causes lactose intolerance the symptoms for this include nausea, bloating, and diarrhea to name a few. This enzyme is produced commercially as a dietary supplement to help them digest the lactose”[3].
The purpose for this experiment is to study the enzyme specificity and if its function is under the influence of environmental factors such as pH and temperature. To test the specificity we used lactase in several test tubes in the presence of lactose and sucrose to figure out which one would result with the highest concentration of glucose, which is one of the lactase products. The test tubes each contained, milk (lactose), or sucrose, and either lactase enzyme or water, which is used as a negative control.
We hypothesized that the enzyme is specific, and will break down lactose, but not sucrose. We then found out our hypothesis is accurate because it proved that enzyme lactase is specifically hydrolyzed lactose. The test tube containing milk and lactase is the only one that contained glucose; the others containing sucrose and lactase did not.
Biology 5: Enzyme Lab Report ...
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... is closest to body temperature (25°C); boiling water (100°C) denatures the enzyme, and that the enzyme is not able to function properly if it is placed in ice (4°C). Both test tubes D. 4°C (100mg/dL) and E.25°C (300mg/dL) release glucose results while test tube F.100 °C releases absolutely no glucose concentration.
Completing this experiment helped us get a better understanding of enzymes. Observing and recording enzymatic reactions was very helpful, nothing compared to learning about them in a book or in a PowerPoint, this took time and research to get accurate facts. This experiment helped us to understand how specific lactase really is and how different each test tubes reaction came to be. Completing this lab report helped me to understand how important lactase is and for future experiments it taught me how to make valid hypothesis and predictions.
This indicated that the effect of high temperature on the activity of peroxidase was irreversible and so if the optimum temperature was restored the enzyme activity will not increase again because denaturation resulted in a permanent change in the shape of the active site of the peroxidase enzyme. In conclusion, the results of this experiment supported the hypothesis that enzymes including peroxidase enzyme are sensitive to temperature changes[George
Living organisms undergo chemical reactions with the help of unique proteins known as enzymes. Enzymes significantly assist in these processes by accelerating the rate of reaction in order to maintain life in the organism. Without enzymes, an organism would not be able to survive as long, because its chemical reactions would be too slow to prolong life. The properties and functions of enzymes during chemical reactions can help analyze the activity of the specific enzyme catalase, which can be found in bovine liver and yeast. Our hypothesis regarding enzyme activity is that the aspects of biology and environmental factors contribute to the different enzyme activities between bovine liver and yeast.
For example, if a person had been able to consume lactose products for their life with no problems, but in an unfortunate event had to have a portion of his or her small intestine removed, there would be a change in the number of present lactase enzymes in the stomach. Because the lactase enzyme is stored in the small intestine, the person may now experience lactose intolerance due to the decrease in the presence of lactase. Knowing where the lactase enzyme is stored can aid physicians in understanding what will happen after a procedure or the introduction of a new medication. The experiment was conducted to determine the optimal ph of lactose required to produce the maximum amount of glucose. It was predicted that the optimal ph of lactose would be most efficient at lactose ph 6, and that the lower the ph, the amount of glucose produced would increase
For example, incubating the samples at different temperatures would create more data points to establish an optimal temperature. From the results in the experiment in this study, it is known as temperature increases, enzymatic activity increase, and vise versa. However, what can not be observed is at what point does the increase in temperature begin to denature the enzyme, above 60°C. Furthermore, assays can be preformed to determine optimal pH, as well. From Dutta’s, and his partners, experiment it shows that there is a range where the Heliodiaptomus viduus’s lactase shows the most activity, which is between 5.0 and 6.0
While the tube for specimen Cb turned a tannish white in the lower half of the tube while the top stayed the lavender inoculated tube color. Do to this evidence I determined that both specimens Ca and Cb cannot use the process Casein hydrolysis or Casein coagulation due to lack of soft or firm curds in both tubes. Since there was no casein curds formed, I concluded that specimens Ca and Cb also cannot perform the process of proteolysis. My conclusion is supported by the fact that there was no clearing of the medium. I have also determine that neither of my organisms can make the enzymes rennin, proteolytic or even proteases. I know my specimens cannot produce proteases due to the fact that there was no blue coloring in the tubes which means that the byproduct Ammonia was not produced to increase the pH. Since neither of my specimens can make these enzymes, I concluded that my specimens cannot break down lactose or casein. Although I did learn that specimen Cb can reduce litmus due to the evidence that the lower part of the tube turned a tannish white color with a purple ring at the top. This color change from a purple to a white means that the litmus was reduced turning it clear and leaving the white of the milk to show. Finally I know that specimen Ca cannot reduce litmus due to the fact that the tube had no change in
Lactase is an enzyme found in the digestive system. It is essential to the complete digestion of sugar in whole milk and milk products. Lactase specifically breaks down lactose, a complex sugar. Lactase cannot be absorbed by the body unless it is broken down by lactase into glucose and galactose. According to webMD, “Lacking lactase in their intestines, a person consuming dairy products may experience the symptoms of lactose intolerance…Abdominal cramping, flatulence (gas) and diarrhea can occur when a lactose intolerant person consumes milk products.” ("Lactase Enzyme oral : Uses, Side Effects, Interactions, Pictures, Warnings & Dosing - WebMD", n.d.) Lactase is not recommended for use in CHILDREN younger than 4 years of age. Safety and effectiveness in this age group have not been confirmed. (Kluwer, 2014)
LI was first recognized in the 1960s when researchers found black children responding unfavorably to milk in their diets (Harrison 812). Research led to the discovery that lactose, the major sugar in milk and related dairy products, was undigestible in some people because they were missing the enzyme lactase. Lactase breaks down lactose into its component monosaccharide sugars, glucose and galactose. In people missing lactase, lactose passes undigested through the small intestine. In some people, the undigested lactose passes through the remainder of their systems with no ill effects. In others, however, the undigested lactose becomes viscous and ferments in the colon (Englert and Guillory 903). The thickness of the liquid and the fermentation cause painful cramping, gas and sometimes diarrhea. Besides not being able to digest lactose, these people suffer from malabsorption, which causes them to receive little or none of milk's nutrients (Houts 110).1
Purpose: The purpose of this lab is to explore the different factors which effect enzyme activity and the rates of reaction, such as particle size and temperature.
The independent variable for this experiment is the enzyme concentration, and the range chosen is from 1% to 5% with the measurements of 1, 2, 4, and 5%. The dependant variable to be measured is the absorbance of the absorbance of the solution within a colorimeter, Equipments: Iodine solution: used to test for present of starch - Amylase solution - 1% starch solution - 1 pipette - 3 syringes - 8 test tubes – Stop clock - Water bath at 37oc - Distilled water- colorimeter Method: = == ==
However, the decrease varied depending on the temperature. The lowest temperature, 4 degrees Celsius, experienced a very low decrease of amylose percentage. Temperature at 22 degrees Celsius and 37 degrees Celsius, both had a drastic decrease in amylose percentage. While the highest temperature, 70 degrees Celsius, experienced an increase of amylose percentage. In conclusion, as the temperature increases the percentage of amylose decreases; however, if the temperature gets too high the percentage of amylose will begin to increase. The percentage of amylose increases at high temperatures because there is less enzyme activity at high temperatures. However, when the temperature is lower, more enzyme activity will be present, which results in the decrease of amylose percentage. This is why there is a decrease of amylose percentage in 4, 22, and 37 degrees Celsius. In this experiment the optimal temperature is 37 degrees Celsius, this is because this is the average human body temperature. Therefore, amylase works better at temperatures it is familiar
Hypothesis: If a test tube filled with 3% hydrogen peroxide and catalase solution, the room temperature will increase the activity. Freezer, refrigerator, and boiling water will have
Enzymes are types of proteins that work as a substance to help speed up a chemical reaction (Madar & Windelspecht, 104). There are three factors that help enzyme activity increase in speed. The three factors that speed up the activity of enzymes are concentration, an increase in temperature, and a preferred pH environment. Whether or not the reaction continues to move forward is not up to the enzyme, instead the reaction is dependent on a reaction’s free energy. These enzymatic reactions have reactants referred to as substrates. Enzymes do much more than create substrates; enzymes actually work with the substrate in a reaction (Madar &Windelspecht, 106). For reactions in a cell it is important that a specific enzyme is present during the process. For example, lactase must be able to collaborate with lactose in order to break it down (Madar & Windelspecht, 105).
This lab attempted to find the rate at which Carbon dioxide is produced when five different test solutions: glycine, sucrose, galactose, water, and glucose were separately mixed with a yeast solution to produce fermentation, a process cells undergo. Fermentation is a major way by which a living cell can obtain energy. By measuring the carbon dioxide released by the test solutions, it could be determined which food source allows a living cell to obtain energy. The focus of the research was to determine which test solution would release the Carbon Dioxide by-product the quickest, by the addition of the yeast solution. The best results came from galactose, which produced .170 ml/minute of carbon dioxide. Followed by glucose, this produced .014 ml/minute; finally, sucrose which produced .012ml/minute of Carbon Dioxide. The test solutions water and glycine did not release Carbon Dioxide because they were not a food source for yeast. The results suggest that sugars are very good energy sources for a cell where amino acid, Glycine, is not.
Their table had 15 mL glucose, 10 mL RO water, and 10 mL of yeast which they then placed in an incubator at 37 degrees Celsius. In conclusion, I feel that the absence of RO water in the flask made the enzymes work a little harder than when the RO water was in the mixture of the flask. Comparison #4 is between the Controlled Table and Table #5. The mixture for that table’s flask was 15 mL Sucrose, 10 mL of RO water and 10 mL of yeast, which the flask was then placed in an incubator at 37 degrees Celsius.
Enzymes are protein molecules that are made by organisms to catalyze reactions. Typically, enzymes speeds up the rate of the reaction within cells. Enzymes are primarily important to living organisms because it helps with metabolism and the digestive system. For example, enzymes can break larger molecules into smaller molecules to help the body absorb the smaller pieces faster. In addition, some enzyme molecules bind molecules together. However, the initial purpose of the enzyme is to speed up reactions for a certain reason because they are “highly selective catalysts” (Castro J. 2014). In other words, an enzyme is a catalyst, which is a substance that increases the rate of a reaction without undergoing changes. Moreover, enzymes work with