CP12 Guide Lines Biology A Level Tutor
Activity 5.18
Guide Lines for Core practical 12: Enzyme Activity.
Investigating the effect of temperature on enzyme activity
Core practical instructions given by Pearson can be found at this link:
https://qualifications.pearson.com/content/dam/pdf/A%20Level/biology-a/2015/teaching-and-learning-
materials/A_level_Biology_A_Core_Practical_12_-_Effect_of_Temperature_on_Rate.pdf
Content:
1. Basic information on enzyme activity and Q10
2. Planning and Experimental Design
3. Health and Safety
4. Make a plan
5. Perform the experiment
6. Analysis and interpretation of data
7. Conclusion and evaluation
8. Write the report!
9. Sample of Data (Statistical test & Analysis)
1/15
, CP12 Guide Lines Biology A Level Tutor
Point 1: Research the background science
What are you investigating?
Core practical 12, investigates the activity of catalase over a range of
temperatures. The substrate for catalase is hydrogen peroxide and the products of
its decomposition are water and oxygen. Hydrogen peroxide is a reactive oxygen
species and by-product of several biochemical reactions. Since hydrogen peroxide
becomes toxic if it accumulates, catalase protects cells from oxidative damage.
The rate of reaction is monitored by the rate of appearance of the product oxygen.
How do changes in temperature effect enzymes:
From 0oC up to the optimum, as the temperature increase the rate of the
reaction increases, as the enzyme and the substrate gain more kinetic energy. Thus,
as temperature increases, the number of collision between the enzyme and the
substrate increase, thus the number of enzyme-substrate complexes formed
increases. At the optimum temperature the rate of the reaction is the highest, as the
enzyme and the substrate collide more often and produce more enzyme-substrate
complexes. At temperature higher than the optimum, the rate decreases as the
enzyme denatures. The active site losses its shape, thus, the substrate cannot fit into
it any longer.
What is Q10
The Q10 temperature coefficient is a measure of the rate of change of a rate of
reaction as a consequence of increasing the temperature by 10 °C. Q10 is a unitless
quantity, as it is the factor by which a rate changes, and is a useful way to express
the temperature dependence of a process.
2/15
Activity 5.18
Guide Lines for Core practical 12: Enzyme Activity.
Investigating the effect of temperature on enzyme activity
Core practical instructions given by Pearson can be found at this link:
https://qualifications.pearson.com/content/dam/pdf/A%20Level/biology-a/2015/teaching-and-learning-
materials/A_level_Biology_A_Core_Practical_12_-_Effect_of_Temperature_on_Rate.pdf
Content:
1. Basic information on enzyme activity and Q10
2. Planning and Experimental Design
3. Health and Safety
4. Make a plan
5. Perform the experiment
6. Analysis and interpretation of data
7. Conclusion and evaluation
8. Write the report!
9. Sample of Data (Statistical test & Analysis)
1/15
, CP12 Guide Lines Biology A Level Tutor
Point 1: Research the background science
What are you investigating?
Core practical 12, investigates the activity of catalase over a range of
temperatures. The substrate for catalase is hydrogen peroxide and the products of
its decomposition are water and oxygen. Hydrogen peroxide is a reactive oxygen
species and by-product of several biochemical reactions. Since hydrogen peroxide
becomes toxic if it accumulates, catalase protects cells from oxidative damage.
The rate of reaction is monitored by the rate of appearance of the product oxygen.
How do changes in temperature effect enzymes:
From 0oC up to the optimum, as the temperature increase the rate of the
reaction increases, as the enzyme and the substrate gain more kinetic energy. Thus,
as temperature increases, the number of collision between the enzyme and the
substrate increase, thus the number of enzyme-substrate complexes formed
increases. At the optimum temperature the rate of the reaction is the highest, as the
enzyme and the substrate collide more often and produce more enzyme-substrate
complexes. At temperature higher than the optimum, the rate decreases as the
enzyme denatures. The active site losses its shape, thus, the substrate cannot fit into
it any longer.
What is Q10
The Q10 temperature coefficient is a measure of the rate of change of a rate of
reaction as a consequence of increasing the temperature by 10 °C. Q10 is a unitless
quantity, as it is the factor by which a rate changes, and is a useful way to express
the temperature dependence of a process.
2/15
