Question 22M.2.HL.TZ1.b
| Date | May 2022 | Marks available | [Maximum mark: 2] | Reference code | 22M.2.HL.TZ1.b |
| Level | HL | Paper | 2 | Time zone | TZ1 |
| Command term | Compare and contrast | Question number | b | Adapted from | N/A |
In winter when temperatures drop, brown bears (Ursus arctos) enter a cave and hibernate. The graph shows the mean values for the body temperature, heart rate and activity of 14 brown bears throughout the year. The grey shaded areas indicate the periods when the bears are in transition between hibernation and normal activity.
[Source: Adapted from Evans, A.L., Singh, N.J., Friebe, A., Arnemo, J.M., Laske, T.G., Fröbert, O., Swenson, J.E. and Blanc,
S., 2016. Drivers of hibernation in the brown bear. Frontiers in Zoology, 13(7). This article is distributed under the terms of the
Creative Commons Attribution 4.0 International License (http://creativecommons.org/licenses/by/4.0/).]
Compare and contrast the changes in mean ambient and body temperatures during 2012.
[2]
Accept one similarity:
- both rise and then fall / both fall with hibernation and rise with activity
- both reach minimum during hibernation and maximum during activity;
- both lowest in January/February / both rise from January/February;
Accept one difference:
- one peak of ambient temp but body temp has two peaks / OWTTE;
- body temp remains maximal for longer/plateaus whereas ambient peaks;
- body temperature is always higher than ambient temperature;
- ambient range is greater than body temperature range / OWTTE;
Many candidates realized that they were expected to give similarities and differences between the curves, but most struggled to do this clearly. Rather than make eclectic statements about the data that may be correct but are not significant, the aim with a question such as this is to make comments that would allow someone who has not been shown the curves to sketch them. Some students confused maxima or minima with increases and decreases, so for example stating that ambient body temperature increased in July, when it reached a maximum in July and stopped increasing.
