Question

What is diaphragm ?? ​

Answer 1

The diaphragm, a dome-shaped muscle at the base of the lungs, plays an important role in breathing — though you may not be aware of it. When you inhale, your diaphragm contracts (tightens) and moves downward.

This creates more space in your chest cavity, allowing the lungs to expand.

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Answer 2

The muscular structure present between thoracic cavity and abdominal cavity is called  diaphragm. It forms the floor of the chest cavity and helps in inhalation and exhalation during  breathing.