Solved UPSC CDS/OTA Question
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Q · Respiratory System Medium · 45s
Which of the following structures is the primary site of gas exchange in the lungs?
TopicRespiratory System
Question Typemultiple choice
DifficultyMedium
Marking+1 / −0.33
Test Duration30 min
Step-by-Step Solution
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The alveoli are tiny air sacs in the lungs where oxygen and carbon dioxide are exchanged between the air and the blood. Their thin walls and large surface area make them ideal for gas exchange.
Final Answer: Option C - Alveoli