Solved UPSC CDS/OTA Question
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Q · Respiratory System medium · 45s
Which muscle is primarily responsible for breathing?
TopicRespiratory System
Question Typemultiple choice
Difficultymedium
Marking+1 / −0.33
Test Duration30 min
Step-by-Step Solution
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The diaphragm is a dome-shaped skeletal muscle separating thoracic and abdominal cavities. During inhalation, it contracts and flattens, increasing thoracic volume. While intercostals assist by elevating ribs, the diaphragm provides about 75% of tidal volume change and is therefore the principal muscle of respiration.
Final Answer: Option B - Diaphragm