Unit 2: Form and Function
Topic 2.6: Gas Exchange Questions
Practice 20 exam-style questions for IB Biology Topic 2.6. Review the question stems below, then unlock the full Question Bank to access markschemes, model answers, and AI grading.
1State1 mark
State the name of the pore in a leaf surface through which gases enter and leave the leaf.
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Besides the diaphragm, which muscle group contracts to cause inspiration?
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Which two cells control the opening and closing of a stoma?
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State the name of the muscle group, other than the diaphragm, whose contraction causes inspiration.
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2026
State the type of cell that secretes surfactant in the alveoli.
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State the direct effect that the destruction of alveolar walls in emphysema has on the lung's capacity for gas exchange.
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In a person with emphysema, what happens to the alveoli in the lungs?
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Through which structures do carbon dioxide and oxygen enter and leave a leaf?
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2026
Label a stoma and the two guard cells that surround it.
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State one function of a one-way valve in the breathing circuit of a spirometer.
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2026
Draw a labelled diagram of an alveolus and its capillary.
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On the spirometer trace below, which reading is the tidal volume?
[Diagram: bio-spirometer]
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State the process by which oxygen and carbon dioxide cross the gas-exchange surface in the lungs.
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Which alveolar cell secretes surfactant?
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By what process do oxygen and carbon dioxide cross the gas-exchange surface in the lungs?
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At a gas-exchange surface in a mammalian lung, in which directions do oxygen and carbon dioxide move?
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Which volume can NEVER be read from a spirometer trace?
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Which feature of a HEALTHY alveolus allows fast gas exchange and is lost in emphysema?
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What causes the thorax (chest) to expand during inspiration?
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What happens to the diaphragm when a person breathes out at rest?
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