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A-LevelBiologyGas exchangeMay/June 2023Paper 1 Q371 Mark

The average thicknesses for some structures in the human respiratory system are shown. [Figure 37.1] A molecule of oxygen is in the alveolar air space next to the wall of the alveolus. What is the shortest distance that the molecule needs to diffuse from its current position to the haemoglobin that completely fills a red blood cell in the nearest capillary? (Assume that the red blood cells touch the walls of a capillary.)

A595 nm
B600 nm
C605 nm
D610 nm

✓ Correct Answer

The correct answer is C. This question tests the candidate's understanding of gas exchange within the Biologysyllabus. The examiner's mark scheme requires...

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Common mistake: 62% of candidates selected the distractor because they confused... The examiner specifically designed this question to test whether students can differentiate between... To secure full marks, candidates must demonstrate...

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About This A-Level Biology Question

This multiple-choice question appeared in the Cambridge A-Level Biology (9700) May/June 2023 examination, Paper 1 Variant 2. It tests the topic of Gas exchange and is worth 1 mark.

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