Enzyme Lab Report

Only available on StudyMode
  • Download(s) : 163
  • Published : October 30, 2012
Open Document
Text Preview
The major objective of this experiment was to observe the effects of catalase under varying controlled conditions. The scope of this experiment includes Metabolic processes, such as cellular respiration, and it poisonous byproduct hydrogen peroxide. The methodology includes procedures; multiple variables were tested in specific concentrations; that test the reaction rates of the enzyme catalase over a fixed period of time. The major conclusion was that catalase reacts faster in warm temperatures that are neither freezing nor boiling, catalase performs well in lower concentrations than the substrate, and catalase prefers neutral pH levels around 7.

Enzymes are proteins that catalyze metabolic reactions vital for the survival and functioning of cells [1]. Without enzymes, metabolic processes would occur at unfeasible rates. Catalase is a naturally occurring enzyme that breaks down hydrogen peroxide into water and oxygen; it is essential to cellular respiration. I asked if enzyme activity was affected when exposed to different conditions, such as temperature, substrate concentration, and pH levels. My first hypothesis is that higher temperatures amplify catalyzation, although too high of a temperature denatures enzymes. My second hypothesis is that smaller concentrations of enzyme in the enzyme to substrate concentration ratios produce higher reactions. The last hypothesis is that enzyme reactions work best at a neutral pH. I observed and recorded the effect of these conditions on catalase.

The enzyme catalase is important because it handles the decomposition of approximately half of generated H2O2 in living organisms [2]. It is important for biologists to understand catalase because all cells produce hydrogen peroxide, and its the job of catalase to break it down. This research will help increase the knowledge of enzyme activity in complex environments, and under what conditions the enzyme catalase will perform best.

Materials and Methods
The materials used in this experiment included 4 test tubes (5 for pH), catalase, hydrogen peroxide, an ice water bath, a warm water bath, a boiling water bath, thermometer, test tube rack, a wax pencil, a metric ruler, a timing device, and pH solutions at 1, 4, 7, 10 and 13. Three different experiments were tested in this lab; temperature, substrate concentration and pH.

In the temperature experiment, I filled all 4 test tubes with 3 centimeters of hydrogen peroxide and 2 centimeters of catalase, and then labeled them 1) Room Temperature(20°C), 2) Ice(0°C), 3) Body Temperature(37°C), and 4) Boiling(100°C). The positive control of this experiment was the test tube kept in room temperature, and the negative control was the test tube placed in the ice. The independent variables of this experiment were time and temperature, and the dependent variable was the amount of reaction that occurred. Each test tube was left at the designated temperature for two minutes, and then afterwards were tested every ten seconds for a minute. My technique included swirling the test tube 3 times each after every ten seconds, and then I would record the bubble height in centimeters.

In the Substrate concentration experiment, I filled the test tubes with different enzyme to hydrogen peroxide concentrations, which were measured in centimeters. Next, I labeled the test tubes accordingly; 1) 1(cm):4(cm), 2) 2:3, 3) 3:2, and 4) 4:1. The positive control of the experiment was the test tube with the 1:4 ratio of enzyme to substrate concentration, and the negative control was the 4:1 ratio of enzyme to substrate concentration. The independent variables were time and the ratio of enzyme to substrate concentration and the dependent variable was the amount of reaction that occurred. Each test tube was left at room temperature and then tested every ten seconds for a minute. The technique used was the same as experiment one.

In the pH experiment, I filled all 5 of the beakers...
tracking img