Home › CBSE Class 11 › Biology › Breathing and Exchange of Gases › Emphysema is most commonly caused by
Emphysema is most commonly caused by
Aviral pneumonia in childhood
Bchronic cigarette smoking
Ca single severe asthma attack
Dhigh-altitude residence over months
Answer & Solution
Correct answer: B. chronic cigarette smoking
Emphysema is a chronic obstructive disease in which alveolar walls are destroyed, lowering gas-exchange surface area. Long-term cigarette smoking is overwhelmingly the leading cause; alpha-1 antitrypsin deficiency is rare. Vital capacity drops and residual volume rises.
Related questions
A stone-crusher works for years in dust and develops lung fibrosis. Such workers should weWheezing from inflamed bronchi and bronchioles is:The enzyme in red cells that speeds up carbon dioxide and water turning into bicarbonate iEvery 100 mL of oxygenated blood delivers about ___ of oxygen to the tissues.Oxygen binds haemoglobin in the lungs and leaves it at the:Haemoglobin is red because it contains:About 97 percent of oxygen in blood is carried by:Gases cross from alveoli to blood mainly by: