DP Biology (last assessment 2024)
Question 18M.3.HL.TZ2.3b
| Date | May 2018 | Marks available | [Maximum mark: 1] | Reference code | 18M.3.HL.TZ2.3b |
| Level | HL | Paper | 3 | Time zone | TZ2 |
| Command term | State | Question number | b | Adapted from | N/A |
b.
[Maximum mark: 1]
18M.3.HL.TZ2.3b
The graph shows the effect of relative humidity on the transpiration rate in Chinese privet (Ligustrum sinense).
The rate of water uptake was measured using the potometer shown in the diagram. The diameter of the capillary tube is 1 mm.
(b)
State a variable that needs to be controlled in this experiment.
[1]
Markscheme
temperature
OR
atmospheric pressure
OR
solar radiation/light
OR
wind speed
OR
leaf area
OR
size of plant
Do not accept humidity.
