To Investigate The Effect Of Temperature On

The Enzyme Catalase Essay, Research Paper

investigate the effect of temperature on the enzyme Catalase. 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 2H̶̶̶̶̶̶̶̶₂O₂

——->H₂O + O₂ + heatPLAN ????????? 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 tubeUsing 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 don?t 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°C. I predict that the enzymes optimum temperature is 23°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°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°C the enzyme will be denatured and will no longer

work. For this reason few cells can tolerate temperatures higher than

approximately 45°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

EQUATIONSUBSTRATE? ENZYME?

PRODUCTS 2H₂O₂????? Catalase?? 2H₂O

+ O₂

+ 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 (°c) AMOUNT OF O₂ RELEASED (ml) Test 1 Test 2 Test 3 4 4

4? 4 0°c

(crushed ice) 5°c 23°c

(room temp) 40°c 50°c 100°c(boiling

point) ????????? As you can

see from the results table we will be taking six measurements of the

temperature ranging from (0°c to 100 °c). I predict that the enzyme will be

totally denatured at 100°c and will no longer be active. We also predict that

the optimum temperature of this enzyme is 23°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°c. We? predict that the enzyme may take up to 15-30

minutes to completely denature at 60°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 1ml of distilled water. The reaction may have reacted too fast

with 2ml of Hydrogen Peroxide, so we diluted it with one part water. *Measure 2ml 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. ?RESULTS TIME TEMPERATURE (°c) AMOUNT OF O₂ RELEASED (ml) Average (mins) Test 1 Test 2 Test 3 6.3 6.7 4 4

4? 4 0°c

(crushed ice) 5°c 23°c

(room temp) 40°c 50°c 100°c(boiling

point) 6 7.3 8.2 7.7 5.2 0 6.1 7.4 8.4 7. 5.3 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°c rise doubles

the rate of enzyme activity. This is only true up to an optimum temperature,

however beyond this point (usually 40°c) the 3D 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°c). It was after 50°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. In many cases a rise

in 10°C will double the rate of reaction in a cell. 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. 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