Describe4 marksStandard
The alveoli in human lungs are lined with squamous epithelium. Describe the features of this epithelium that make it well adapted for efficient gas exchange between alveolar air and blood.
CAIE A Level Biology 9700 · Gas exchange
Gas exchange: describe question
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
- 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…
- 4 marks · Describe the roles of ciliated epithelial cells and goblet cells in maintaining the health of the gas exchange system.
- 5 marks · A student is studying the human gas exchange system. She traces the path of an oxygen molecule from the trachea to the blood. Describe the…
- 5 marks · Explain the pathway of an oxygen molecule as it moves from the trachea into the blood of a pulmonary capillary. In your answer, name the…
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