Conclusions

Conclusions

Even though our results were different from what we expected, we were still able to understand bradycardia. Also, the physiology associated with the dive reflex was easy to understand through trying to manipulate the results with varying test conditions.

Conclusions

As lung volume increased, the elastic recoil did likewise to allow generation of greater expiratory pressures. Conversely, during inspiration there was a decrease in pressure generated at increased lung volume due to the length tension relationship of the inspiratory skeletal muscles. Surface tension decreases as the lung is stretched, which induces greater compliance.

Muscular effort can generate pressures of greater magnitude than elastic recoil. The capacity of respiratory muscles to induce such large changes in pressure is vital to facilitate rapid maintenance of P_O2. Differences in the experimental curves from the expected PV curves are due to inconsistencies in breathing technique, muscle fatigue, systematic errors and most importantly biological variability. 

The maximum expiratory PV curve does not share the same pattern of compliance as the maximum inspiratory PV curve as each process uses a different set of muscles. This property is called hysteresis and was evident in the results. FRC is significant because it is the volume at which the pressure in the airways is equal to atmospheric pressure. It may be used to measure elastic recoil and compliance to aid in the prognosis of certain conditions.