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A-LevelBiologyGas exchange9700/12 · Feb/Mar 2021 · Q341 Mark

How many times must a molecule of carbon monoxide pass through a cell surface membrane as it diffuses from an air space in an alveolus, through a cell in the capillary wall, into a red blood cell?

A3
B4
C5
D6

✓ Correct answer

C: 5

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About this question

Topic
Gas exchange, A-Level Biology (syllabus 9700). Multiple choice, 1 mark.
Source
A-Level Biology, Feb/Mar 2021 Paper 1 Variant 2, question 34.

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