Effect Of Temperature On The Enzyme Catalase example essay topic

To investigate the effect of temperature on the enzyme Catalase. INTRODUCTION The aim of this experiment is to determine the effects of varying temperatures on enzyme (Catalase). We will conclude the experiment by establishing the enzymes optimum temperature (the temperature at which it works best at). We will also carry out some simple experiments using the substrate Hydrogen Peroxide.

Hydrogen Peroxide + Catalase -- Water + Oxygen 2 HO -- - HO + O + heat PLAN The aim of this experiment is to determine the effect of varying temperature of enzyme Catalase. Apparatus Diagram. Water bath. Thermometer.

Pipette. Stop Clock. Measuring cylinder. Inverted cylinder. Inverted measuring cylinder. Conical Flask / bung.

Delivery tube Using the equipment safely It is important that we use the apparatus carefully, as safety will be an issue through out the whole experiment. We will wear goggles and an apron, to protect our eyes and clothes. As we are using enzymes and Hydrogen Peroxide we need to be extra careful, ensuring they dont come in contact with our eyes and skin. We also must be careful when using hot water, being careful not to burn ourselves. Therefore through out the whole experiment we shall be very careful in our actions around the lab. Catalase is an enzyme found in all living cells.

It makes Hydrogen Peroxide decompose into water and oxygen. We will measure the amount of Oxygen released from the Hydrogen Peroxide. In order to do this we will use an inverted measuring cylinder. This piece of apparatus measures the amount of Oxygen given off, measuring in (ml).

This will help us measure the amount of Oxygen more accurately. To make the test fair the following parameters must remain constant during the experiment. These parameters are water, Hydrogen Peroxide, Catalase, room temperature and the duration of the reactions. If the reaction reacts too quickly we may dilute the solution. By insuring this test is fair, we will gain accurate results. Variables Dependant Variable: rate of breakdown of Hydrogen Peroxide, time Independent Variable: temperature of solution.

Control Variable: Volume of Hydrogen Peroxide, volume of Catalase solution, concentration of Hydrogen Peroxide, concentration of Catalase. HYPOTHESIS I predict that the breakdown of Hydrogen Peroxide will be quicker when the temperature is increased until it exceeds 40^0 C. I predict that the enzymes optimum temperature is 23^0 C (room temperature). This is because a rise in temperature increases the rate of most chemical reactions and a fall in temperature will slow them down. In many cases a rise in 10^0 C will double the rate of reaction in a cell. This is particle theory. I am going to investigate the temperature at which reactions occur.

I predict an increase in temperature will result in an increase in kinetic energy. Since the speed of particles increases, they should collide more often and therefore the speed of reaction increases. The particles will also have more energy thereby speeding up the reaction even more. It has been suggested that for every 10 degree rise in temperature, the speed of the reaction will double. At low temperatures particles of reacting substances do not have much energy. However, when the substances are heated, the particles take in energy.

This causes them to move faster and collide more often. The collisions have more energy, so more of them are successful. Therefore the rate of reaction increases. The more successful the collisions are the faster the reaction. The same can be said for reactions controlled by enzymes, but because enzymes are proteins if the temperature exceeds 50^0 C the enzyme will be denatured and will no longer work. For this reason few cells can tolerate temperatures higher than approximately 45^0 C. Enzymes are specific in the reactions they catalyse, much more so than inorganic Catalysts.

Normally, a given enzyme will Catalyse only one reaction, or type of reaction. The enzyme has an active site that helps it to recognise its substrate in a very specific way. Just like a key only fits into a specific lock, each enzyme has its own specific lock, each enzyme has its own specific substrate. This is called the lock and key theory. The enzymes never actually get consumed in the process, they just increase the rate of reactions.

When enzymes denature the heat starts to destroy their shape and structure. The shape of the enzyme is so important to its working that any change in the shape of the molecules will make them less effective or stop them working completely. Therefore I predict that by heating the Hydrogen Peroxide, when it reacts with the enzyme the shape of the enzyme will be ruined due to the high temperature. So the higher the temperature of the Hydrogen Peroxide and Catalase solution, the less effective the reaction will be. THE EQUATION SUBSTRATE ENZYME PRODUCTS 2 HO Catalase 2 HO + O + heat We will be measuring three main factors: -.

Temperature-the optimum temperature of the enzyme... Oxygen-the amount released from the Hydrogen peroxide... Time- the duration of the reaction. The room temperature may be a factor that will affect our results. Therefore we will have to try our bests to insure the test is carried out under the same conditions.

This includes the room temperature. To make it fair we will allow the reactions to have the same amount of time to occur. We will change the TEMPERATURE of the Hydrogen Peroxide. This is what our results table will look like TIME (mins) TEMPERATURE (^0 c) AMOUNT OF O RELEASED (ml) Test 1 Test 2 Tes 0^0 c (crushed ice) 5^0 c 23^0 c (room temp) 40^0 c 50^0 c 100^0 c (boiling point) As you can see from the results table we will be taking six measurements of the temperature ranging from (0^0 c to 100 ^0 c). I predict that the enzyme will be totally denatured at 100^0 c and will no longer be active. We also predict that the optimum temperature of this enzyme is 23^0 c (room temperature), the enzyme may still react but not as much as it would with a lower temperature.

Enzyme molecules can take a little while to denature, even over 60^0 c. We predict that the enzyme may take up to 15-30 minutes to completely denature at 60^0 c, by which time the reaction has already finished. To help obtain the best possible results I will repeat each experiment three times and then find the average set of data to plot on my graph. Our measurements will be very precise as we will carry out the experiment as safely and fairly as possible.

We are using accurate apparatus to allow us to achieve this. INVESTIGATION EXPERIMENT I am going to investigate how the enzyme, Catalase reacts at different temperatures. The procedure for the experiment is as follows; Set up the apparatus; place water in the water bath, and fix the inverted measuring cylinder so that the delivery tube connects it to the conical flask. Using a measuring cylinder, measure 1 ml of Hydrogen Peroxide and 1 ml of distilled water. The reaction may have reacted too fast with 2 ml of Hydrogen Peroxide, so we diluted it with one part water. Measure 2 ml of the enzyme, Catalase and add it to the hydrogen peroxide solution in a conical flask.

Immediately place the bung on the conical flask, as the reaction would have already started. Set the timer for 4 minutes. Repeat the experiment three times, (for accuracy), using the different selected temperatures. It is important that only the temperature is changed (of the hydrogen peroxide), since that is what is being investigated. 3 0 6.3 5.5 8.54. 8 0 CONCLUSION My results proved my prediction to be correct.

The breakdown of Hydrogen Peroxide accelerates as the temperature increases until the optimum temperature after which it begins to slow down. Temperature influences the rate of enzyme activity. Usually a 10^0 c rise doubles the rate of enzyme activity. This is only true up to an optimum temperature, however beyond this point (usually 40^0 c) the 3 D shape of the active site becomes distorted and the enzyme becomes inactive.

Cooling or even freezing does not destroy enzymes, though it slows down their activity. From studying the graph and our results table we can see the enzymes optimum temperature (23^0 c). It was after 50^0 c where we could see a decrease in the enzymes activity. a rise in temperature increases the rate of most chemical reactions and a fall in temperature will slow them down. This is particle theory. We investigated the temperature at which reactions occurred. We predicted that an increase in temperature would result in an increase in kinetic energy.

We were correct, since the speed of particles increases, they should collide more often and therefore the speed of reaction increases. EVALUATION Overall I would like to think our experiment went successfully. Everything went according to plan. We followed out our safety instructions and did the experiment fairly and accurate as possible. Therefore our results came out to be reliable and accurate. Due to using the equipment safely and accurately this experiment has been successful.

Although there were a few anomalies in the results that did not agree with the scientific information, about enzymes optimum temperatures. When measuring the amount of Hydrogen Peroxide, we may have not measured the exact amount. We could have accidentally measured 1.1 ml, instead of 1 ml. Another problem was the temperature of the room.

As we carried out the experiment on different days, some times the temperature in the room varied, from 23^0 C to 30^0 C. This may have affected the particles in the enzymes, causing the reaction to occur slightly faster than it should. Luckily there were no spillages with the Hydrogen Peroxide or Catalase, as we used the equipment safely and accurately. When adding the Catalase to the Hydrogen Peroxide solution (in the conical flask), we should immediately place the bung on the flask. This is so that no Oxygen.