Breathing and Exchange of Gases Test 8

Emphysema defined as the long-term, progressive disease of the lungs that primarily causes shortness of breath due to over-inflation of the alveoli air sacs in the lung. the lung tissue involved in exchange of gases (oxygen and carbon dioxide) is impaired or destroyed.

Asthma is a common long-term inflammatory disease of the airways of the lungs. Symptoms include episodes of wheezing, coughing, chest tightness, and shortness of breath. Environmental factors which are responsible for asthma include exposure to air pollution and allergens. The increased asthmatic attacks in certain seasons are due to the inhalation of seasonal pollen. Seasonal pollen is obtained by the dehiscence of pollen grain in a particular season to which a person may be allergic.

So, the correct answer is 'Inhalation of seasonal pollen'.

Respiratory centres are located in the medulla oblongata and pons in the brain. They are extremely sensitive to blood concentration of carbon dioxide and work in response to reduction or elevation in the level of CO₂​ in the body and hence help in regulation of respiration.

Emphysema is a disease of the lungs that usually develops after many years of smoking. Along with asthma and chronic bronchitis, emphysema belongs to a group of lung diseases known as chronic obstructive pulmonary disease (COPD).

The pneumotaxic center is located in the upper part of the pons i.e pons varolii. Its nuclei are the subparabrachial nucleus and the medial parabrachial nucleus. The pneumotaxic center controls both the rate and the pattern of breathing.