DP Biology (first assessment 2025)

Test builder »

Question 19M.2.HL.TZ1.c.i

Select a Test
Date May 2019 Marks available [Maximum mark: 1] Reference code 19M.2.HL.TZ1.c.i
Level HL Paper 2 Time zone TZ1
Command term Define Question number c.i Adapted from N/A
c.i.
[Maximum mark: 1]
19M.2.HL.TZ1.c.i

B. subtilis colonies form biofilms through quorum sensing. Define quorum sensing.

[1]

Markscheme

«a system of» behaviours triggered as a function of population density ✔

Examiners report

This question was a good discriminator, as weaker students were unable to use correct terminology such as “population density,” instead resorting to vague phrases like “when the bacteria sense something.”

Syllabus sections