Question 21M.2.HL.TZ2.3b
| Date | May 2021 | Marks available | [Maximum mark: 2] | Reference code | 21M.2.HL.TZ2.3b |
| Level | HL | Paper | 2 | Time zone | TZ2 |
| Command term | Outline | Question number | b | Adapted from | N/A |
A broad bean is the seed of a species, Vicia faba, in the Fabaceae, a family of flowering plants. This family contains many species that are used as sources of food.
An experiment was done to test the hypothesis that temperature affects the rate of germination of the broad bean. Outline two factors apart from temperature that should be controlled in this experiment.
[2]
a. same amount/type of soil/substrate / pH of soil ✔ e.g.: heater
b. same amount of water / humidity ✔
c. oxygen/aeration ✔
d. same measurement of germination / time ✔ e.g.: emergence of radicle
e. same number/source/age of seeds ✔
Accept discussion of light only in as much as it relates to temperature.
Several answers considered how light is needed for germination without any reference to its relationship to temperature.
