Question 21N.2.SL.TZ0.c
| Date | November 2021 | Marks available | [Maximum mark: 2] | Reference code | 21N.2.SL.TZ0.c |
| Level | SL | Paper | 2 | Time zone | TZ0 |
| Command term | Explain | Question number | c | Adapted from | N/A |
Explain the effect of temperature on the rate of photosynthesis in this mesocosm.
[2]
rate of photosynthesis increases as temperature rises because:
a. temperature is the limiting factor for photosynthesis;
b. higher temperatures increase enzyme activity;
c. faster molecular motion/more molecular kinetic energy/more frequent enzyme-substrate collisions;
d. Calvin cycle/light independent reactions (of photosynthesis) speed up;
About half candidates merely stated the relationship shown in the graph, rather than actually explaining it. An explanation based on enzyme activity were expected. Performance in this question and in (d) correlated well with the overall performance of each candidate on the paper, probably because biological understanding was required. Other parts of question 1 were less well correlated, as is typical for data analysis questions.
