DP Biology (last assessment 2024)
Question 19N.3.SL.TZ0.2a
| Date | November 2019 | Marks available | [Maximum mark: 1] | Reference code | 19N.3.SL.TZ0.2a |
| Level | SL | Paper | 3 | Time zone | TZ0 |
| Command term | State | Question number | a | Adapted from | N/A |
a.
[Maximum mark: 1]
19N.3.SL.TZ0.2a
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.
[Source: Cruz R, et al. Properties of a new fungal β-galactosidase with potential application in the dairy industry.
Revista de Microbiologia 30: 265–271, 1999]
(a)
State another independent variable that would affect the activity of this enzyme.
[1]
Markscheme
temperature
OR
lactose/substrate concentration
OR
Inhibitors / cofactors ✔
Do not accept pH or acidity.
