Respiratory Physiology - Defence Systems of the Lung

Question 1

Atmospheric pollutants

Answer 1

Carbon monoxide 50%

Sulfur oxides 15%

Nitrogen oxides 14%

Hydrocarbons 15%

Particulates 5%

Photochemical oxidants

Question 2

Consequence of Sulfur and Nitrogen oxides

Answer 2

Acid rain

Question 3

Most common source of atmospheric pollutants

Answer 3

Transportation especially cars

Can be reduced with catalytic converters

Also cigarette smoking

Question 4

Photochemical oxidants

Answer 4

Contribute to smog

Slow reaction - smog usually a distance away from source of hydrocarbons due to wind moving them before smog forms

Question 5

Mechanisms of aerosol deposition in the lungs with particle size and most common site

Answer 5

Sedimentation is gravitational

Question 6

Clearance of deposited particles from the lung

Answer 6

Mucociliary system

Alveolar macrophages

Question 7

Mucocilliary system

Answer 7

Mucus produced by mucus glands and goblet cells

Question 8

Motion of action of cillia

Answer 8

Question 9

Structure of cilia

Answer 9

Made up of series of microtubules

Question 10

Impairment of normal mucociliary function: Mucus

Answer 10

Too much mucus - ciliary escalator can no longer function as mucus layer too thick

Eg Chronic bronchitis, Cystic fibrosis

Question 11

Impairment of mucociliary function:
Cilia

Answer 11

Paralysis of cilia - eg. toxic gases (eg. chlorine gas)

Bronchial epithelium destruction

Congenital defect of ciliary motion - dyskinesia eg. Kartagener’s syndrome

Question 12

Impairment of macrophage function

Answer 12

Inhaled gases - eg ozone, cigarette smoke

Toxic particles - eg silica

Alveolar hypoxia or radiation

Corticosteroids

Alcohol ingestion