DP Biology (last assessment 2024)

Test builder »

Question 20N.2.SL.TZ0.c

Select a Test
Date November 2020 Marks available [Maximum mark: 2] Reference code 20N.2.SL.TZ0.c
Level SL Paper 2 Time zone TZ0
Command term Outline Question number c Adapted from N/A
c.
[Maximum mark: 2]
20N.2.SL.TZ0.c

The photomicrograph below shows the protozoan Paramecium caudatum.

[Source: Deuterostome, CC BY-SA 3.0
https://creativecommons.org/licenses/by-sa/3.0, via Wikimedia Commons.]

Outline one aspect of how P. caudatum carries out homeostasis.

[2]

Markscheme

a. lives in fresh water so water enters cell (by osmosis);

b. contractile vacuoles collect and expel water;

c. homeostasis is keeping internal conditions within limit/constant / involves osmoregulation/regulating water content/potential;

Syllabus sections