LABORATORY REPORT
Activity 9: Regulation of Pulmonary Ventilation
Name:
Instructor:
Date:
PREDICTIONS
1. Hypercapnia (high arterial carbon dioxide partial pressure) causes minute ventilation to
2. Hypoxemia (low arterial partial pressure) causes minute ventilation to
MATERIALS AND METHODS
1. Dependent variable
2. Independent variable
3. Controlled variables
4. As pCO2 levels were increased, the concentration of a gas in the inhaled air was decreased in
order to maintain the oxygen levels. Name that gas.
RESULTS
See Table 3: Effect of Hypercapnia on Pulmonary Ventilation
See Graph 1a: Effect of Inhaled Carbon Dioxide on Minute Ventilation
See Graph 1b: Effect of Inhaled Carbon Dioxide on Arterial Carbon Dioxide Partial Pressure
See Graph 1c: Effect of Inhaled Carbon Dioxide on Arterial Oxygen Partial Pressure
See Graph 1d: Effect of Inhaled carbon Dioxide on Arterial pH
1. State whether increasing the amount of carbon dioxide in inhaled air increased, decreased or
did not change minute ventilation from normal.
2. What is the minute ventilation when inhaled air contains 5% carbon dioxide?
3. State whether increasing the amount of carbon dioxide in inhaled air increased, decreased or
did not change arterial pCO2 from normal.
4. What is the arterial pCO2 when inhaled air contains 5% carbon dioxide?
5. State whether increasing the amount of carbon dioxide in inhaled air increased, decreased or
did not change arterial pO2 from normal.
6. What is the arterial pO2 when inhaled air contains 5% carbon dioxide?
7. State whether increasing the amount of carbon dioxide in inhaled air increased, decreased or
did not change plasma pH from normal.
8. What is the arterial blood pH when inhaled air contains 5% carbon dioxide?
See Table 4: Effect of Hypoxemia on Pulmonary Ventilation
See Graph 2a: Effect of Inhaled Oxygen on Minute Ventilation
See Graph 2b: Effect of Inhaled Oxygen on Arterial Carbon Dioxide Partial Pressure
See Graph 2c: Effect of Inhaled Oxygen on Arterial Oxygen Partial Pressure
See Graph 2d: Effect of Inhaled Oxygen on Arterial pH
9. State whether increasing the amount of oxygen in inhaled air increased, decreased or did not
change minute ventilation from normal.
10. What is the minute ventilation when inhaled air contains 16% oxygen?
11. State whether increasing the amount of oxygen in inhaled air increased, decreased or did
not change arterial pCO2 from normal.
12. What is the arterial pCO2 when inhaled air contains 16% oxygen?
13. State whether increasing the amount of oxygen in inhaled air increased, decreased or did
not change arterial pO2 from normal.
14. What is the arterial pO2 when inhaled air contains 16% oxygen?
15. State whether increasing the amount of oxygen in inhaled air increased, decreased or did
not change plasma pH from normal.
16. What is the arterial pH when inhaled air contains 16% oxygen?
DISCUSSION
1. Discuss the relationship between CO2 and pH and their affect on minute ventilation.
2. Discuss how inhaling increased amounts of CO2 affects pulmonary ventilation.
3. Discuss how inhaling decreased amounts of O2 affects pulmonary ventilation.
4. Discuss how plasma pH affects the hemoglobin saturation curves and the amount of oxygen
delivered to the tissues.
5. Restate your predictions that were correct and give data from your experiment that support
them. Restate your predictions that were not correct and correct them with supporting data
from your experiment.
APPLICATION
A small child announces to her parents that she is going to hold her breath until they let her
watch more television.
1. Explain how the child's blood carbon dioxide, hydrogen ions, and bicarbonate ions levels
change during breath holding.
2. If she continues to hold her breath, will she pass out? Explain.