22) i. Explain how the thoracic chamber is a closed chamber.
ii. Why is such a setup necessary?
iii. Why is the larynx called the sound box?

Dear Student
The lungs are situated in the thoracic chamber. The thoracic chamber need to be a closed chamber as it is involved in inspiration and expiration which requires a fixed volume. As any change in the thoracic volume will reflect in pulmonary volume and will affect the functioning of other systems.Hence thoracic chamber is a closed chamber .
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