Experiment 4 and 5

Experiment 4: Data Table 1

Volume measurement (L)

Individual (L) Class average

(Male) (L)

Class average (Female)

(L)

Tidal Volume (TV) .2 .2 .2

Inspiratory Reserve (IRV) .2 .5 .2

Expiratory Reserve (ERV)

.3 .4 .3

Vital Capacity (VC) .4 1.1 .4

Residual Volume (RV) ≈1.5 ≈1.5 ≈1.5

Total Lung Capacity (TLC)

2.6 2.6 2.6

Experiment 4: Analysis 1) What was your Tidal Volume (TV)? What would you expect your TV to

be if you inhaled a foreign object which completely obstructed your right mainstream bronchus?

My tidal volume was .02, if I were to completely obstruct my right mainstream bronchus it would cut the TV in half, to .1.

2) Describe the difference between lung volumes for males and females. What might account for this?

The only differences in our class averages were in the IRV, ERV, and the VC. This is because of the size difference in male and female

thoracic cavity dimensions. The males who did it and had a cavity size closer to the females who performed the experiment had

less differences in their data. 3) Calculate your Minute Volume at rest. If you are taking shallow

breaths (TV = 0.20 L) to avoid severe pain from rib fractures, what respiratory rate will be required to achieve the same minute volume?

.02 x 14 = 2.8, a person taking shallow breathes breathing rate would increase to compensate for the decrease in TV.

Experiment 4: Analysis Cont.4) Exposure to occupational hazards such as coal dust, silica dust, and

asbestos may lead to fibrosis, or scarring of lung tissue. With this condition, the lungs become stiff and have more “recoil.” What would happen to TLC and VC under these conditions?

They would both decrease because the lungs aren’t able to properly expand, therefore their breathing rate would increase to compensate.5) In severe emphysema there is destruction of lung tissue and

reduced recoil. What would you expect to happen to TLC and VC?The TLC would remain the same because the RV increases due to extra air extra air left in the person’s lungs while the VC would decrease because the person is unable to properly exhale the air in their lungs.6) What would you expect to happen to your Expiratory Reserve

Volume when you are treading water in a lake?It would increase due to the strain of treading water because body has an increased need for oxygen. This causes the breathing rate to increase causing the person’s exhales to be increasingly powerful.

Experiment 5: DataTable 1

Holding Breath Rapid Breathing

Before Challenge

Tidal volume (L) 1.2 .08

Respiratory rate (breaths/min) 3.9 3.5

Initial minute ventilation (L/min) 4.7 0.28

After Challenge

Tidal volume (L) .08 1.2

Respiratory rate (breaths/min) 3.3 5.5

Minute ventilation (L/min) .26 6.6

Experiment 5: Data Cont.Table 2–Exercise

Before Challenge

Tidal volume (L) .16

Respiratory rate (breaths/min) 4.2

Minute ventilation (L/min) .67

During Challenge

Tidal volume (L) 2.5

Respiratory rate (breaths/min) 3.2

Minute ventilation (L/min) 8

After Challenge

Tidal volume (L) .82

Respiratory rate (breaths/min) 3.9

Minute ventilation (L/min) 3.2

Experiment 5: Analysis1) Describe the changes in respiratory rates, tidal volumes, and minute

ventilations that occurred after each of the following physiologic challenges in terms of CO2 levels and their effect on respiratory drive:

(a)breath holding – After holding your breath the tidal volume, respiratory rate, and minute ventilation was lower than it was before.

(b)rapid breathing – After rapid breathing the tidal volume, respiratory rate, and minute ventilation was higher than it was before with normal breathing.

(c) exercise – After exercise the tidal volume, respiratory rate, and minute ventilation increase and was higher than before without the exercise.

2) Which challenge caused the greatest change in respiratory rate (pre-challenge vs. post challenge)? Tidal volume? Minute ventilation? Did respiratory rate or tidal volume change the most relative to its resting value?

The greatest change in respiratory rate was when he was rapid breathing. The greatest change in tidal volume was holding breath. And the greatest change in minute ventilation was rapid breathing. The tidal volume changed the most from what its resting value was.

Experiment 5: Analysis Cont.3) How might breathing into a paper bag help someone who is extremely anxious

and hyperventilating?Breathing into a paper bag can help someone who is anxious and

hyperventilating because when they breathe into the bag and exhale into the bag the levels of CO2 are increased in the bag, and it helps bring more CO2 into the body and bloodstream and make your PH normal.4) Some patients with severe emphysema have constant high levels of CO2 because

of inadequate ventilation. The central nervous system breathing center in these patients becomes insensitive to CO2 and more dependent on the level of O2, which is low. These patients are said to have “oxygen-dependent respiratory drive.” What might happen if you give such a person high levels of supplemental O2?

If you give them high levels of O2 it should help balance out the need for both CO2 and O2, making the oxygen-dependent state slowly go away.5) Would breathing pure O2 help the air hunger experienced by athletes who have

just completed a race? Why or why not?Breathing pure O2 after a race doesn’t help athletes any more than just

breathing the regular air afterwards. They are feeling the air hunger because of the overuse of their muscles causing a buildup of lactic acid in the muscles and blood.