Introduction
Enzymes are organic catalysts that speed up chemical reactions within the body. Enzymes are specific for one particular reaction or group of related reactions. Enzymes are large globular protein molecules with one or more indentations on their surface called active sites, an active site is the part of the enzyme that binds to the substrate, the active site has a specific shape that will bind to a specific substrate. For an enzyme to catalyse a reaction the small substrate molecules must temporarily bind to the active sites of the enzymes were the bonds in the substrate are broken and the products released.
The liver of a sheep has an optimal temperature of 39 oC. This being said it was only about 21-22 oC in the biology lab,
…show more content…
Cut a small cube of liver which will fit easily into a measuring cylinder
2. Place 2 mL of hydrogen peroxide into a 10-mL measuring cylinder and add 3 drops of detergent
3. Place the cube of liver into the hydrogen peroxide using forceps and at the same time start the stopwatch
4. Record the volume of the foam in the measuring cylinder after 2 minutes
Results
Table 1 – class results of catalase activity Temperature Group 1 Group 2 Group 3 Group 4 Class average mL
Ice 28 49 60 36 43.25
Room Temperature 68 27 31 25 37.75
Hot Water 47 36 55 31 42.25 The class group average comprised of 4 groups.
The amount of foam from the catalytic reaction was measured in mL from all of the groups was comprised to the table above. The data from all of the four groups do not support the hypothesis.
All results are quantitative. The individual data’s pattern differs greatly from the average group data, being almost a reflection. The average group data forms a positively skewed bell curve; however, it does not have greatest amount of foam produced with the hot water temperature is not the greatest, with the ice temperature, the complete, contrary as to what was taught is
…show more content…
Since the results did not follow the hypothesis, and that there should have been less frothing due to the lower amount of kinetic energy and more frothing at the higher temperature, with greater kinetic energy.
The liver was already cut and this could have made the liver sizes disproportionate to the other ones in the different groups. The amount of hydrogen-peroxide and detergent used may not have been the correct amount as there was a possibility of a parallax error.
To fix random errors within this experiment is to repeat the experiment, so that the results can be accurate and reliable.
Systematic errors were also within the experiment, these included:
• The equipment being faulty- not calibrated- in this case the beaker that was supplied to the different groups, it wouldn’t be precise.
• The instrument used to measure to cut the cube to the size could be wrong and give different enzyme reaction
In the experiment we used Turnip, Hydrogen Peroxide, Distilled Water, and Guaiacol as my substances. On the first activity, Effect of Enzyme concentration of Reaction Rate for low enzyme concentration, we tested three concentrations of the turnip extract, and hydrogen peroxide. For the Turnip Extract I used 0.5 ml, 1.0 ml, and 2.0 ml. For hydrogen peroxide we used 0.1 ml, 0.2 ml, and 0.4 ml. We used a control to see the standard, and used a control for each enzyme concentration used. The control contains turnip extract and the color reagent, Guaiacol. We prepared my substrate tubes separately from the enzyme tubes. My substrate tube
One possible source of error that can affect the results was that a mercury thermometer was used instead of an electronic one. The use of a mercury
Drop the yeast sphere into the graduated cylinder. As soon as the sphere touches the surface of the hydrogen peroxide, start the timer. Each person should be responsible for a concentration.
8. The Hydrochloric Acid was carefully poured into the beaker with the Sodium Thiosulfate. Once the liquids had made contact, three seconds were waited until the stop watch was started.
However, this was not the case. Discrepancies occurred between the two sets of values due to experimental errors. Some of the sources of error during the experiment include: drift on the voltmeter that affected the accuracy of measurements (instrumental error), rounding-off errors during calculations and the old resistance box. However, these errors can be eliminated by using a new functional resistance box, recording readings at right angles, and using four decimals in calculations to avoid rounding off errors.
The experiment is repeated twice and an average is obtained. This ensures the consistency of the measurement as the reading is triplicated, thus reducing anomalies. It can be seen that the reading obtained were around the same value. This proves that the results are reliable.
Enzymes are defined as catalysts that speed up chemical reactions but remain the same themselves. The shape of an enzyme enables it to receive one type of molecule and that specific molecule will fit into the enzyme’s shape. Where a substance fits into an enzyme is called the active site and the substance that fits into the active site is called a substrate. Several factors affect enzymes and the rate of their reactions. Temperature, pH, enzyme concentration, substrate concentration, and the presence of any inhibitors or activators can all affect enzymes. Temperature can affect enzymes because if the temperature gets too high, it can cause the enzyme to denature. pH can affect an enzyme by changing the shape of the enzyme or the charge properties of the substrate so that either the substrate cannot bind to the active site or it cannot undergo catalysis. Every enzyme has an ideal pH that it will strive in. Increasing substrate concentration increases the rate of reaction because more substrate molecules will be interacting and colliding with enzyme molecules, so more product will be formed. Inhibitors can affect enzymes and the rate of their reactions by either slowing down or stopping catalysis. The three types of inhibitors include competitive, non-competitive, and substrate inhibition.
The experimental error in this lab included the question whether the digital scale was as precise as it could be, how the cooling time affected the water in the hydrates, and any miscalculations that could have occurred. The digital scale could have been more precise since they are more precise scales that could deliver more accurate masses in this lab.
In conclusion, the more baking that was added in the reaction the more gas that was produced. When there was only one scoop of baking soda, the least amount of gas was produced, when three scoops of baking soda were used, the most amount of gas was produced. The number of bubbles roughly stayed the same, so the number of bubbles created was not affected by the amount of baking soda. With increments of 1 scoop of baking soda, small amounts of gas are produced each trial. We compared each trial by identifying the firmness of the bag due to the gas. Since gas takes up space of the bag, the more firm the bag is, the more gas is produced. Therefore, our hypothesis of having more baking soda will make more gas is correct.
Enzymes are a key aspect in our everyday life and are a key to sustaining life. They are biological catalysts that help speed up the rate of reactions. They do this by lowering the activation energy of chemical reactions (Biology Department, 2011).
“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].
To begin(control data and experiment data), fill the solution container with designated amount of live yeast and 10 mL of hydrogen peroxide. Quickly after mixing solutions together, cap the container with the cork and straw and cover the open end of the straw. Have one member of the lab begin the timer. Keep the open end of the straw covered to submerge the solution container under water in the tub and let the open end of the straw be placed inside the open end of the graduated
Abstract: Enzymes are catalysts therefore we can state that they work to start a reaction or speed it up. The chemical transformed due to the enzyme (catalase) is known as the substrate. In this lab the chemical used was hydrogen peroxide because it can be broken down by catalase. The substrate in this lab would be hydrogen peroxide and the enzymes used will be catalase which is found in both potatoes and liver. This substrate will fill the active sites on the enzyme and the reaction will vary based on the concentration of both and the different factors in the experiment. Students placed either liver or potatoes in test tubes with the substrate and observed them at different temperatures as well as with
Did the other groups? Did we all have the same equipment? Had it been calibrated so that everyone started with the same baseline? What about the water itself? Did it all come from the same source? What else could possibly influence the outcome of this experiment? Another hour passed quickly as we discussed hundreds of possibilities for the variations in our recorded results. At the end of our lab session, we were assigned our first 10-page lab report for the term. Ten pages on taking the temperature of boiling water!? How would we manage to get ten pages out of this simple assignment? It turns out that ten pages was conservative.
Although the experiment was successful, some errors occurred during the experiment that made most values to deviate from the expected ones. Generally, both fixed and random errors were observed (Mitchell & Worledge, 2015). The random errors, in this case, resulted into statistical fluctuations in the measured data because of the limitations in precision measurement. Additionally, the random errors occurred due to inability to take the same measurements as the expected ones. Furthermore, fixed errors were responsible for reduced inaccuracies in the values obtained (Valiani & Caleffi, 2011). However, the best way to minimize random errors is by averaging