DP Biology (first assessment 2025)
Question 21M.1A.SL.TZ1.12
Date | May 2021 | Marks available | [Maximum mark: 1] | Reference code | 21M.1A.SL.TZ1.12 |
Level | SL | Paper | 1A | Time zone | TZ1 |
Command term | Question number | 12 | Adapted from | N/A |
12.
[Maximum mark: 1]
21M.1A.SL.TZ1.12
What is the term for the attraction of water molecules to other water molecules?
A. Surface tension
B. Capillary action
C. Cohesion
D. Adhesion
[1]
Markscheme
C
Examiners report
It was pleasing to see that three quarters of candidates knew that attraction between water molecules causes cohesion and far fewer incorrectly chose adhesion. These two terms are sometimes treated by candidates as though their meanings are interchangeable, but cohesion is attraction between water molecules and adhesion is attraction to a surface.
