The Effect of Temperature on the Action of Peroxidase Enzyme
Aim
To find the effect of temperature on an enzyme in this case
peroxidase, by studying it decomposing hydrogen peroxide.
Planning
I am measuring the amount of gas given off in the reaction. By
collecting this figure I can determine the rate of reaction. If I know
the rate of reaction I can find out what temperature peroxidase works
best at.
Equipment
· Trough
· Clamp
· 100ml measuring cylinder
· Stop clock
· 10ml measuring cylinder
· Delivery tubes
· Bung
· Conical flask
Variables
Change
The temperature of the reactants:
60
50
40
30
20
10
Control
Amount of peroxidase (10ml)
Amount of hydrogen peroxide (20ml)
Length of experiment (2min)
Time between measurements (15sec)
Equipment used
Safety
I will keep my safety goggles on at all times to prevent painful eye
injury.
Method
For accuracy I am using six different temperatures and I will repeat
the whole experiment twice.
I will record my results in a table. I will then transfer those
figures into two line graphs showing gas given off against time. Using
these I can then work out the rates of reaction for both experiments
and find the averages from the results. Taking the averages I will
plot them against the temperatures the experiments were conducted at.
By doing this I can finds the temperatures that peroxidase works best
at.
Doing the experiment
1. Set up the equipment as shown in the diagram.
2. Heat the peroxidase and hydrogen peroxide separately to the
required temperature.
3. Mix the hydrogen peroxide and the peroxidase in a conical flask,
replace the bung quickly.
4. Begin timing.
5. Record the amount of gas given off every fifteen seconds.
6.
Rinse your beaker thoroughly to wash any excess powder. 12. Repeat steps 7-11 3 more times for reliability. To make sure the temperature still stays hot by continue heating the water a little bit using the hot plate. 13.
Animal metabolism consists of the utilization of nutrients absorbed from the digestive tract and their catabolism as fuel for energy or their conversion into substances of the body. Metabolism is a continuous process because the molecules and even most cells of the body have brief lifetimes and are constantly replaced, while tissue as a whole maintains its characteristic structure. This constant rebuilding process without a net change in the amount of a cell constituent is known as dynamic equilibrium (Grolier1996). In the combustion of food, oxygen is used and carbon dioxide is given off. The rate of oxygen consumption indicates the energy expenditure of an organism, or its metabolic rate (Grolier1996).
The Effect of Temperature on an Enzyme's Ability to Break Down Fat Aim: To investigate the effect of temperature on an enzyme’s (lipase) ability to break down fat. Hypothesis: The graph below shows the rate increasing as the enzymes get closer to their optimum temperature (around 35 degrees Celsius) from room temperature. The enzyme particles are moving quicker because the temperature increases so more collisions and reactions occur between the enzymes and the substrate molecules. After this the graph shows the rate decreasing as the enzymes are past their optimum temperature (higher than). They are getting exposed to temperatures that are too hot and so the proteins are being destroyed.
This experiment was conducted to determine the effects of pH and temperature on peroxidase from a potato. The optimum temperature for peroxidase was determined to be 23°C, because it had a rate of absorbance of 0.3493, higher than the other temperatures evaluated. A temperature of 48°C is inefficient of speeding up peroxidase activity because its rate of absorbance was 0.001.
To make this a fair test, we need to keep the same all variables that
This enzyme speeds up the break down of hydrogen peroxide into water and oxygen, as enzymes are biological catalysts. [IMAGE]The reaction: Hydrogen peroxide Water + Oxygen Catalase -------- [IMAGE] 2H2O2 2H2O + O2 Apparatus: Hydrogen Peroxide, Several sticks of celery, Stand, boss and clamp, 100ml conical flask, 25cm3 burette, 1800cm3 beaker, Rubber bung with delivery tube, Distilled water, Large container filled with water, 10cm3 measuring cylinder, 10cm3 syringe, 20cm3 syringe, Blender, Knife, Ceramic tile, Electronic balance (correct to 2 decimal places), Sieve, Stopwatch/timer. The variables: There are many possible variables in this investigation, such as pH, temperature, the concentration of substrate and the concentration of the enzyme.
The Effect of Temperature on the Activity of the Enzyme Catalase Introduction: The catalase is added to hydrogen peroxide (H²0²), a vigorous reaction occurs and oxygen gas is evolved. This experiment investigates the effect of temperature on the rate at which the enzyme works by measuring the amount of oxygen evolved over a period of time. The experiment was carried out varying the temperature and recording the results. It was then repeated but we removed the catalase (potato) and added Lead Nitrate in its place, we again tested this experiment at two different temperatures and recorded the results. Once all the experiments were calculated, comparisons against two other groups were recorded.
I shall be measuring how much gas is given off. This will be done by measuring the amount of froth on the surface of the liquid. The oxygen released is collected in the form of these bubbles. The equation for the reaction is: (catalase) [IMAGE] H2O2 2H2O + O2 (hydrogen peroxide) (2 part water) (oxygen) I will change the concentration of H2O2 and O2 (making sure the volume stay the same, when one part of a H2O2 particle is taken, an O2 particle is added. Prediction
The temperature effect is reversible in the case whereby the peroxidase is exposed to temperatures that negatively affect its function. This is through addition of many substrates to the active sites of the enzyme to enhance its activity. From the experiment, it is illustrated from graph in figure 2 with the constant slope from temperature of 40 C to320 C. further increase of temperature to 600C led to the reduction of the activity of the enzyme on the dye as a result of denaturing effect thus less color
The Effect of a Catalase on the Breakdown of Hydrogen Peroxide Aim To follow the progress of a catalysed reaction by measuring the volume of gas produced as the reaction proceeds. Using the initial rates of a series of experiments I will be able to find the orders of the reaction with respect to enzyme and substrate. Also to find out if concentration has an effect on the reaction when an enzyme is used to accelerate the breakdown of hydrogen peroxide.
Influence of Temperature on the Activity of Potato Catalase Hypothesis That the higher the temperature the higher the reaction rate of potato catalyse to a point were denaturing occurs in the enzyme and the reaction rate of the potato catalase drops off. Prediction The rate of Catalase activity will be faster at higher temperatures until a point, because at higher temperatures there are more chances of collisions between the enzyme's (Catalase) active site and the substrate (hydrogen peroxide). However the rate depends on the active site being able to join with the substrate, and at higher temperatures the enzyme can be denatured, which changes the shape of the active site which thus prevents the reaction from happening. At first, as the temperature increases the activity of the Potato catalase also increases this is because the collision rate of the enzyme with the hydrogen peroxide is increased.
= = = == I predict that as the concentration of the hydrochloric acid decreases the rate of reaction will decrease and therefore the time taken for 75ml of gas to be released will increase.
2. Step 2: Heat the mixture: Make sure the agarose dissolves. Wait until it boils and when you are going to transfer the mixture, wear gloves to avoid getting burnt. Transfer the mixture to a removable gel tray. 3.
The pH of the solution would alter the rate of the reaction if it was
The aim of this investigation is to: 1) find the rate equation for the reaction between hydrogen peroxide, potassium iodide and sulphuric acid by using the iodine stop clock method and plotting graphs of 1/time against concentration for each variable. Then to find the activation energy by carrying out the experiment at different temperatures using constant amounts of each reactant and then by plotting a graph of in 1/t against I/T, 3) to deduce as much information about the mechanism as possible from the rate equation.