Respiratory Physiology 4

1. When blood circulates through the lung capillaries, it picks up oxygen and a vasodilator agent. Name the vasodilator picked up by the hemoglobin.

Nitric oxide

2. Where is the respiratory centre that generates inspiration at rest located?

Medulla oblongata

3. Name the neurons that generate inspiratory ramp signals.

Dorsal inspiratory group of neurons in medulla oblongata

4. What is the point at which breathing can no longer be voluntarily inhibited called?

Breaking point

5. Where are the central chemoreceptors for control of respiration located?

Medulla oblongata

6. Name the main stimulus that stimulates the peripheral chemoreceptors in the regulation of respiration.

Decreased blood PO2

7. Name the condition due to excessive retention of carbon dioxide in the body.

Respiratory acidosis

8. What is the condition where tissue oxygen levels are low?

Hypoxia

9. What type of hypoxia is due to cyanide poison?

Histotoxic hypoxia

10. Name the condition due to hypoxia combined with increase in PCO2

Hypercapnoea

11. What happens to the compliance of the lungs in the emphysema condition?

It increases

12.  Name the receptors in the lung capillary / interstitium that are stimulated by an increase in the lung interstitial pressure.

J receptors

13. Mount Everest is approximately 29 000 ft or 9 000 m high. What is the atmospheric pressure at the peak?

253 mm Hg

14. Name the instrument used in decompression sickness to rivive the subject to normal.

Caisson’s chamber / hyperbaric chamber

15. What is the normal composition of dry air at sea level?

O2 (21%), CO2 (0.04%), N2 (78.06%) and inert gases (0.1%)

( UMS, 2008 )