Answer:
Because during climbing a flight of stairs our body requires more energy and an increased amount of Carbon Dioxide is produced. to compensate both of these our medulla orders our lungs to breathe faster. In Emphysema extensive lining of alveoli become damaged and hence it can not full fill the demand of the body. hence patient of emphysema becomes short of breath.
Explanation:
Emphysema:
It is the disease in which the patient air sacs becomes damaged due to the thinning of the walls of alveoli. The patient feels short of breath during a tough situation, exercise or during pressure. All those activities which require energy in excessive amount can cause shortness of breath to the emphysema patient.