Skip to main content
A-LevelBiologyGas exchangeFeb/Mar 2023Paper 1 Q361 Mark

Two of the requirements of an efficient gas exchange system are a large surface area and a short diffusion distance. Which row correctly describes how alveoli are adapted to meet these requirements?

Aelastin fibres prevent the alveolus wall from collapsing; an extracellular layer inside the alveolus wall contains blood capillaries
Bgases dissolve in a layer of liquid to speed up diffusion; alveolar walls are next to capillaries
Calveoli are folded and interconnected; walls of alveoli are only one cell thick
Dwalls of alveoli are formed of squamous epithelial cells; red blood cells are very close to capillary walls

✓ 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...

📋 Examiner Report & Trap Analysis

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...

🔒

Unlock the Examiner's Answer

Sign up for free to reveal the correct answer, the official mark scheme breakdown, and the examiner trap analysis for this question.

Sign Up Free to Unlock →

Join thousands of Cambridge students already using Oracle Prep

About This A-Level Biology Question

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

Oracle Prep provides AI-powered practice for all Cambridge O-Level and A-Level subjects. Our platform includes topic predictions with 87.7% accuracy, AI essay grading, and a comprehensive question bank spanning 25 years of past papers.

© 2026 Oracle Prep — The AI-Powered Cambridge Exam Engine