Question
SLPaper 2
The enzyme beta-galactosidase hydrolyses lactose to release glucose and fructose. A study was carried out to determine how acidity affects the activity of a beta-galactosidase enzyme, extracted from the fungus Penicillium simplicissimum.
1.[1]
State another independent variable that would affect the activity of this enzyme.
Verified
Solution
- Temperature
OR - Lactose/substrate concentration
OR - Inhibitors / cofactors;
1 mark
Do not accept pH or acidity.
2.[2]
Outline the measurements which would need to be taken to determine the activity of the beta-galactosidase at different pH values.
Verified
Solution
- Test samples for the concentration/amount of products/glucose/fructose/substrate/lactose;
1 mark - Take samples of the reaction mixture at regular/timed intervals;
1 mark - Repeated measurements «at the different pH values»;
1 mark - Measure independent/controlled/standardised/variables / temperature;
1 mark
Accept use of Benedict/Fehling to see change in amount of reducing sugar.
Must indicate that samples are taken at timed intervals.
