CAIE A Level Biology 9700 · Gas exchange

Gas exchange: describe question

Describe4 marksStandard

Describe the function of each of the following structures in the human gas exchange system:

Cartilage in the walls of the trachea and bronchi
Ciliated epithelium lining the airways
Goblet cells in the airway epithelium
Squamous epithelium of the alveoli

How this question is marked

4 marks, so the mark scheme is looking for about 4 separate creditworthy points. Making the same point twice in different words earns it once.

Describe means: Say what happens or what something is like, in order and with detail. You are not being asked why. If there is data, quote it: name the trend, then give figures with units at the points where it changes.

More Gas exchange questions

4 marks · The trachea and bronchi are lined with a layer of cells that includes ciliated epithelial cells and goblet cells. Describe how these cells…
4 marks · The photomicrograph shows a transverse section through the wall of a bronchus. Describe the distribution and function of each of the…
4 marks · The alveoli in human lungs are lined with squamous epithelium. Describe the features of this epithelium that make it well adapted for…
5 marks · A student looks at transverse sections of a human trachea and a bronchiole. The trachea wall contains C-shaped rings of cartilage and a…
4 marks · Describe the structural features of the squamous epithelium lining the alveoli that are adapted for efficient gas exchange.
4 marks · A student examines a stained section of lung tissue under a light microscope. They observe thin-walled alveoli lined with a single layer…

All Gas exchange questions

Written by Markquill to follow the Cambridge International syllabus. Markquill is independent and is not affiliated with or endorsed by Cambridge International.