DP Biology (last assessment 2024)
Question 19M.3.SL.TZ1.a.iii
| Date | May 2019 | Marks available | [Maximum mark: 1] | Reference code | 19M.3.SL.TZ1.a.iii |
| Level | SL | Paper | 3 | Time zone | TZ1 |
| Command term | Suggest | Question number | a.iii | Adapted from | N/A |
a.iii.
[Maximum mark: 1]
19M.3.SL.TZ1.a.iii
When feed for animals is stored, moisture levels need to be kept low to prevent the growth of fungi. Feed was exposed to 15 % moisture and placed into a respirometer. O2 consumption was monitored using the respirometer over a period of six days.
[Source: © International Baccalaureate Organization 2019]
Other than humidity, suggest a variable that would need to be controlled in this experiment.
[1]
Markscheme
temperature/amount or type of feed «in the respirometer»/amount of CO2 absorber
OR
other reasonable suggestion ✔
Do not accept light
Examiners report
Often more than one answer was given but only the first was marked. Temperature and amount of feed were the most common answers.
