Some pathogens can reach the alveoli, they can still be destroyed by:

1. macrophages in the pulmonary lymph nodes
2. NK cells in the elastic tissues of the lungs
3. cytotoxic T-lymphocytes
4. alveolar macrophages

Which occupational lung disorder can lead to cancer of lung?
1. Silicosis
2. Byssinosis
3. Bagassosis
4. Asbestosis

Involuntary hyperventilation during an anxiety attack can cause the person to become faint because of:
1. increased ${\mathrm{CO}}_2$ levels caused by increase in cellular respiration, reducing brain perfusion and causing ischemia
2. decreased ${\mathrm{O}}_2$ levels in the blood, causing cells to lack enough ATP
3. effects of increased ${\mathrm{O}}_2$ levels in the blood and consequent constriction of cerebral blood vessels
4. lowered ${\mathrm{CO}}_2$ levels in the blood and consequent constriction of cerebral blood vessels

A pulmonary disorder reduces the forced expiratory volume in first second but does not significantly affect the vital capacity. This disorder will be most accurately described as:
1. restrictive lung disorder
2. pulmonary fibrosis
3. pneumoconiosis
4. obstructive lung disorder

“Bends” is a painful condition that is seen in cases of:
1. nitrogen narcosis
2. decompression sickness
3. hyperbaric oxygen therapy
4. carbon dioxide accumulation

Assertion: Infant respiratory distress syndrome[hyaline membrane disease] is the leading cause of death of preterm infants.
Reason: The lungs of infants with respiratory distress syndrome are developmentally deficient in a material called surfactant.

1. Both assertion and reason are true and the reason is the correct explanation of the assertion.
2. Both assertion and reason are true but the reason is not the correct explanation of the assertion.
3. Assertion is true but reason is false.
4. Both assertion and reason are false.