DP Biology (first assessment 2025)

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Question 20N.1B.SL.TZ0.3c

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Date November 2020 Marks available [Maximum mark: 1] Reference code 20N.1B.SL.TZ0.3c
Level SL Paper 1B Time zone TZ0
Command term Suggest Question number c Adapted from N/A
c.
[Maximum mark: 1]
20N.1B.SL.TZ0.3c
(c)

Suggest how a plastic bag placed around the plant pot prevents carbon dioxide from reaching the plant’s leaves.

[1]

Markscheme

a. to prevent CO2 from (organisms in) the soil affecting the experiment;

b. the plastic bag is impermeable to gases;

Examiners report

The plastic bag caused considerable confusion with many candidates stating that it was to prevent carbon dioxide reaching the roots and being taken up the stem to the leaves for photosynthesis.

Syllabus sections