Question

Regarding the assertion and reason, select the right option.

Assertion [A]: Continued smoking over time causes deformation of alveoli.
Reason [R]: Inflammation of air passages due to smoking leads to trapping of the smoke and collapse of alveoli deforming the alveolar chamber.

• A. Both A and R are true and R explains A
• B. Both A and R are true, but R does not explain A
• C. A is true and R is false
• D. Both A and R are false

Answer 1

The correct option is A Both A and R are true and R explains A

Continued smoking leads to destruction of elastic fibers, and the tubular air passages collapse. This causes inhaled air to be trapped partially in the alveolar chamber. The alveolar walls begin to collapse. The walls of the small alveoli fuse together to form sacs. The sacs clump together, deforming the structure of the alveoli. The healthy alveolus has numerous inter chamber walls, which give it a large surface area for efficient absorption of oxygen. Formation of the large sacs thus hampers the normal process of breathing.