Lab Report Enzyme Catalase

This experiment looked at how substrate concentration can affect enzyme activity. In this case the substrate was hydrogen peroxide and the enzyme was catalase. Pieces of meat providing the catalase were added to increasing concentrations of hydrogen peroxide in order to measure the effect of hydrogen peroxide concentrations on the enzyme’s activity. The variable measured was oxygen produced, as water would be too difficult to measure with basic equipment.

When measuring the volumes of Hydrogen Peroxide, Yeast and Water the measurement should be taken by looking at the scale at an angle of 90 degrees to it to avoid any parallax error.

Students will be observing normal catalase reaction, the effect of temperature on enzyme activity, and the effect of pH on enzyme activity in this experiment. The enzymes will all around perform better when exposed in room temperature than when it is exposed to hot and cold temperatures. This is based on the fact that the higher the temperature, the better the enzymes will perform, but as the temperature reaches a certain high degree, the enzymes will start to denature, or lose their function.

Lab six requires students to observe the effects of pH and enzyme concentration on catecholase activity. Enzymes are organic catalysts that can affect the rate of a chemical reaction depending on the pH level and the concentration of the enzyme. As pH comes closer to a neutral pH the enzyme is at its greatest effectiveness. Also at the absorbance of a slope of 0.0122 the enzyme is affected greatly. The pH effect on enzymes can be tested by trying each pH level with a pH buffer of the same pH as labeled as the test tube and 1mL of potato juice, water, and catechol. This is all mixed together and put in the spectrophotometer to test how much is being absorbed at 420nm. As the effect on enzyme concentration can be tested almost the same way. This part of the exercise uses different amounts of pH 7-phosphate buffer and potato juice, and 1mL of catechol mixed together in a test tube. Each substance is put in the spectrophotometer at a wavelength set tot 420nm. The results are put down for every minute up to six minutes to see how enzyme concentration affects reaction rate. The results show that the pH 8 (0.494) affects the enzyme more than a pH of 4 (0.249), 6 (0.371), 7 (0.456), and 10 (0.126). Also the absorbance is greatest at a slope of 0.0122 with test tube C that has more effect on the reaction rate, than test tube A, B, and D.

Procedure Part 1: Observe Normal Catalase Reaction Place a potato cube (3x3x3 cm) into a test tube Add 3 mL of H2O2 into each test tube Allow 1 minute for reaction to occur Record the height in cm of the bubbles Rate how rapidly the solution bubbles on a scale of 0-5 (0=no reaction, 1=slow,...5 =very fast) Part 2: Effect of Temperature on Enzyme Activity Label 3 test tubes: hot, cold, and room temperature Place potato cube (3x3x3 cm) into each test tube Place the test tube labeled hot and cold into the coordinating baths Place the test tube labeled room temperature into the test tube labeled room temperature on the test tube rack Level each test tube in place for 3 minutes After 3 minutes record the temperature of each tube Add 3 mL of H2O2 into each tube After a minute, record the height in cm of the bubbles in each tube Rate how rapidly the solution bubbles on a scale of 0-5 Part 3: Effect of pH of Enzyme Activity Label 3 test tubes acid, base, and pH 7 Place 3 mL of potato catalase into each tube Add 10 drops of vinegar to the test tube labeled acid Add 10 drops of ammonia into the tube labeled base Add 10 drops of distilled water into the tube labeled pH 7 After 2 minutes add 3 mL of H2O2 to each

It is predicted that enzyme activity will speed up from 0 to 37 degrees and then rapidly slow down or stop altogether at 55 degrees. Methods For this experiment the dependent variable will be the amount of product, oxygen, produced by the enzyme catalase breaking down hydrogen peroxide. The independent variable will be temperature. Four temperatures will be tested on the enzyme to see how much product will be produced. Controlled variables will be the amount of enzyme, hydrogen peroxide and water used in the test tubes, as well as the volume of the nalgene bottle (250 mL) used in testing to measure the product.

Test tube two had water with a ph of 7.0 and then hydrogen peroxide, and to the third test tube was water with a pH of 11 and hydrogen

Subtracting the initial volume of the syringe from the final volume will determine the amount of H₂O₂ present. Subtracting the amount of peroxide present from the baseline will determine how much was used during the trial.

We could use the H2O4 because acids will interfere with hydrogen bonds and other IMFs in the enzyme which would denature it, permanently making the enzyme unable to work. The catalase was the enzyme that acted on the product, which was hydrogen peroxide (H2O2). And of course, the hydrogen peroxide, or H2O2, was the substrate and the catalase was the enzyme.Our results seemed to be consistent because once we added the necessary amount that was needed to determine the amount of H2O2 in the solution, the color of the solution afterwards would always be a light, clear brown, as opposed to having various colors and shades each time. This means that we added the correct, proportional amount of potassium permanganate each time. In comparison to the class data, less of our H2O2 was decomposed. For example, for the trial for 30 seconds, 0.6 mL of our H2O2 was decomposed while the average for the class data was 2.22

We used a computer and a gas pressure sensor to measure the production of oxygen gas as hydrogen peroxide was destroyed by the enzyme catalase at various enzyme concentrations, pH values, and substrate concentrations. We then put 3 mL of water and 3 mL of 3% H2O2 (hydrogen peroxide) to our four test tubes as well as different amounts of catalase drops to each test tube. For the second trial, we added 3 mL of 3% H2O2 and pH Buffer as well as 2 drops of enzyme solution. Lastly, for our last trial we added different amounts of 3% H2O2 and water. We concluded that as pH increases, the rate of enzyme activity decreases and this can be seen in the graphs since when the pH was 10, the rate of enzyme activity was the lowest at 0.3513.

I will conduct the experiment by marking my test tubes 1-4. Making sure the proportions of solutions are the same and warming all the test tubes equally to 40c. Using the balloon and string method, I would expose the enzymes to their respective pH solution for 10 minutes (combining the two). Afterwards, I will use string in order to measure the amount of oxygen is created in mm; although, I would first funnel the mashed potatoes solution into the balloons and release the catalase when all balloons successfully attach with zip-ties. The purpose of the zip tie is to keep the balloons completely secured, allowing me flip the test tube upside down if needed, to get a complete

The overall purpose of the lab was to study an enzyme found in the liver called catalase and how its rate of reaction was dependent on the specific conditions surrounding it. The research question provided for this lab was: “How do pH, temperature and surface area affect the action of catalase?”

Background Information An enzyme is a “macromolecule serving as a catalyst, a chemical agent that increases the rate of a reaction,” (Campbell Biology, 68). There are many different enzymes that have varying effects on reactions. Catalase, “an enzyme that brings about (catalyzes) the reaction by which hydrogen peroxide is decomposed to water and oxygen,” is the primary enzyme that effects hydrogen (Encyclopedia Britannica). In this experiment, the goal is to test how three different locations where these enzymes can be found catalyze the reactions in hydrogen peroxide. When hydrogen peroxide is exposed to certain enzymes it starts to become water due to the loss of oxygen molecules.

Catalase Experiment In many cases, the body needs a way to break down proteins, enzymes, and even poisons. In this case our main goal within this experiment was to break down hydrogen peroxide. When you add an enzyme called, catalase, and it will break hydrogen peroxide down into water and oxygen gas. As the lab went on we were trying to test the activity between catalase and hydrogen peroxide (the action of the enzyme in the environment).

This experiment is designed to analyze how the enzyme catalase activity is affected by the pH levels. The experiment has also been designed to outline all of the directions and the ways by which the observation can be made clearly and accurately. Yeast, will be used as the enzyme and hydrogen peroxide will be used as a substrate. This experiment will be used to determine the effects of the concentration of the hydrogen peroxide versus the rate of reaction of the enzyme catalase.