RP1- Investigstion Into The Effect Of Temperature On The Rate Of Reaction Catalysed By Trypsin

Question 1

What factors influence the rate of reaction of an enzyme-controlled reaction?

Answer 1

Temperature, pH, concentration of the substrate, concentration of the enzyme

These factors can be studied by changing one variable at a time while keeping others constant.

Question 2

What is the purpose of control samples in the experiment?

Answer 2

To indicate the absence of enzyme activity and to show the colour of a completely hydrolysed sample

One control uses distilled water and the other uses hydrochloric acid.

Question 3

What is the first step in the method for measuring the effect of temperature on enzyme activity?

Answer 3

Make two control samples

This involves adding milk suspension and either distilled water or hydrochloric acid to flat bottomed tubes.

Question 4

What is the temperature range used in the experiment to test the enzyme activity?

Answer 4

10°C, 20°C, 30°C, 40°C, 50°C
These temperatures are used to determine the rate of reaction.

Question 5

How long should the milk samples be equilibrated in the water bath?

Answer 5

5 minutes

This is done before adding trypsin to the samples.

Question 6

What is the role of trypsin in the experiment?

Answer 6

To hydrolyse the milk samples
Trypsin is added simultaneously to all test tubes after equilibration.

Question 7

What should be recorded during the experiment?

Answer 7

How long it takes for the milk samples to completely hydrolyse and become colourless

This data is essential for calculating the rate of reaction.

Question 8

Fill in the blank: The rate of reaction is calculated using the formula: Rate of reaction = _______.

Answer 8

1/mean time
The mean time refers to the average time taken for hydrolysis at each temperature.

Question 9

Why is it important to keep all other variables constant during the experiment?

Answer 9

To ensure they do not influence the results
This helps in accurately determining the effect of the variable being tested.

Question 10

Conclusion

Answer 10

• milk contains a protein called casein which, when broken down, causes the milk to turn colourless. Trypsin is a protease enzyme which hydrolyses the casein protein
• as the temperature increases from 10^C, kinetic energy increases so more enzymes substrate complexes form. This means that the rate of reaction increases up to the optimum temperature.
• At temperatures beyond the optimum, bonds in the enzyme structure break which changes the shape of the active site. This means that the substrate and enzyme and no longer complementary.