Biology 0610 · IGCSE · Gas exchange in humans

Gas exchange in humans — practice question

Which row indicates the approximate percentage composition of gases in expired air?

  • Apercentage of carbon dioxide 12, percentage of oxygen 9
  • Bpercentage of carbon dioxide 4, percentage of oxygen 16
  • Cpercentage of carbon dioxide 24, percentage of oxygen 24
  • Dpercentage of carbon dioxide 27, percentage of oxygen 20

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