DP Biology (first assessment 2025)
Question SPM.2.HL.TZ0.a
Date | May Specimen-2023 | Marks available | [Maximum mark: 4] | Reference code | SPM.2.HL.TZ0.a |
Level | HL | Paper | 2 | Time zone | TZ0 |
Command term | Describe | Question number | a | Adapted from | N/A |
a.
[Maximum mark: 4]
SPM.2.HL.TZ0.a
Describe how toxins such as DDT might concentrate in the bodies of birds.
[4]
Markscheme
- some toxins/DDT are persistent/degrade slowly (once released into the environment);
- (some toxins/DDT) enter the food chain through producers/lower trophic levels;
- (some toxins/DDT) are passed on to higher trophic levels in the food chain;
- (they are) difficult to excrete / are not excreted;
- (they) accumulate in fatty tissues of animals;
- higher trophic levels/top consumers have higher/the highest concentration of pesticides in their bodies;
- they bioaccumulate/biomagnify;
