Enzyme Lab

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.

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.

This investigation will be carried out to investigate the rate of reaction of the enzyme catalase on the substrate hydrogen peroxide.

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.

The hypothesis tested in this experiment was, if the temperature of enzyme catalysis were increased, then the reaction rate would increase, because enzyme-catalysis reacts by randomly colliding with substrate molecules, and the increase in temperature increases the speed of collision or reaction rate. The final data collected for the experiment was positive with my hypothesis. The coffee filter, covered in potato solution, sank and rose at a faster pace in the hydrogen peroxide when the temperatures were raised.

The first experiment begun by filling a 600-ml beaker, almost to the top, with water. Next, a 10-ml graduated cylinder was filled to the top with water. Once water was added to the beaker and graduated cylinder, a thumb was placed over the top of the graduated cylinder. This would ensure that no water was let out and no bubbles were let into the graduated cylinder. Next, it was turned upside down and fully submerged into the beaker. Then, a U-shaped glass tube was attained. The short end of the glass tube was placed into the beaker with the tip inside of the graduated cylinder. Next, a 50-ml Erlenmeyer flask was received. After, 10-ml of substrate concentration and 10-ml of catalase/buffer solution were placed into the flask. A rubber stopper was then placed on the opening of the flask. After adding these, the flask was held at the neck and spun softly

Between 36.7°C and 4° C there was a decrease in reaction rate. This is majorly due to the fact that less enzyme-substrate complexes are formed as the kinetic energy is decreased and both the catalase and hydrogen peroxide have less collisions with one another (“The Kinetic Molecular Theory”). A temperature decrease would have also caused the molecules to be more tightly packed together, thereby reducing the flexibility of catalase, making enzyme-substrate complexes less likely to occur.

The motive of this lab is to attain a better understanding of enzyme activity by timing chemical reactions in certain temperatures and pH levels. Enzymes act as catalysts that help speed up reactions. Without these enzymes chemical reactions in metabolism would be backed up. There are two factors that affect an enzyme’s reaction rate: temperature and pH levels. In this label we will be testing different pH levels and temperatures to see which ones cause the most reactions.

Andra Larade Bio 30 B7 11/20/15 Liver Enzyme Lab The Effect of pH and Temperature on the Efficiency of Catalase Abstract: In order to determine how pH and temperature affect the liver enzyme catalase, an experiment was conducted. Catalase breaks apart hydrogen peroxide producing water and oxygen.

In conjunction, these results prove the hypothesis true. The enzyme activity rate does increase as the enzyme concentration increases. These results were dependent on the amount of catalase solution present in each group. The amount of catalase is the only variable that changed in the experiment; the 10 mL of H2O2, the LabQuest, the bottle, and the paper discs were all the same. Any difference in the results had to be a result of the differing amounts of catalase solution.

BACKGROUND: Catalase (the enzyme) is found in yeast, it breaks down hydrogen peroxide (the substrate) into water and oxygen according to this equation. 2H2O2(aq) -------------------> 2H2O(l) + O2(g) + catalase(aq) One molecule of catalase can break 40 million molecules of hydrogen peroxide each second. Factors that affect the rate of reaction § Increasing the temperature increases the kinetic energy at which the enzyme and substrate collide.

In the lab, tests showed that when the temperature was increased to 37°C the reaction rate rose around 45 ml/min. In room temperature, the reaction rate is only around 30 ml/min. Compared to the room temperature results, the enzymes tested with the warmer temperature had a higher reaction rate. This happened because because catalase enzyme reactions happen when they randomly collide with substrate molecules. When temperature is added, the molecules move faster, and collide more often, resulting in a faster reaction rate.

Assessing Catalase's Rate of Hydrogen Peroxide Decomposition Under Varied Temperatures Through Gas Collection The goal of this lab was to determine the effect of temperature on the reaction rate of catalase. We created stock solutions of homogenized chicken liver, controlled the temperature through a water bath, and added the enzyme catalase to the hydrogen peroxide substrate. We then collected the gas through a water displacement setup and recorded how long each trial took to produce 2 ml, 4 ml, and 6 ml of oxygen. For rate of reaction, we found an initial positive relationship, a peak, and then a potential (not statistically proven) negative relationship as temperature increased past 38˚C. From our t-tests, we found

The purpose of this lab report is to investigate the effect of substrate concentration on enzyme activity as tested with the enzyme catalase and the substrate hydrogen peroxide at several concentrations to produce oxygen. It was assumed that an increase in hydrogen peroxide concentration would decrease the amount of time the paper circle with the enzyme catalase present on it, sowing an increase in enzyme activity. Therefore it can be hypothesised that there would be an effect on catalase activity from the increase in hydrogen peroxide concentration measured in time for the paper circle to ride to the top of the solution.

Testing the Effects of Temperature on the Decomposition of Hydrogen Peroxide with the Enzyme Catalase