Same chapter3 marksDifficulty: Medium
State three differences between inspired and expired air.
The Respiratory System
3 marksDifficulty: Medium
How is an alveolus adapted for gaseous exchange?
Original Khojo Papers practice question — not from a past board paper.
Answer
The alveoli are extremely numerous and so give a vast surface area. Each has a wall only one cell thick and is surrounded by a dense network of capillaries, so the diffusion distance is very short. Their inner surface is moist, so the gases dissolve before diffusing, and the constant blood flow keeps the concentration gradient steep.
No citable source has been recorded for this record. Treat it as practice material, not as fact.
Explanation
The total alveolar surface in an adult is roughly the area of a tennis court.
Related questions
From the same topic and chapter, at a similar level.
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Same chapter2 marksDifficulty: Easy
Name the organs of the human respiratory system in the order in which air passes through them.
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Same chapter2 marksDifficulty: Easy
State two differences between inspired air and expired air.
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