The Enzyme Catalase Essay, Research Paper
To
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
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
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
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.EVALUATION ????????? Overall I would like to think our
experiment went successfully. Everything went according to plan. We followed
out our safety instructions and did theexperiment 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 1.1ml, instead of 1ml. 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°C to
30°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 Catalose to the Hydrogen Peroxide solution (in the conical flask),
we should immediately place the bung on the flask. This is so that no Oxygen
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