DEMONSTRATION OF RESPIRATION 



181 



b') Shake defibrinated blood in bottle containing oxygen. 

 Note result (oxyhemoglobin). 



8) Respiration apparatus: Tie trachea of cat or rat on 

 piece of glass tubing which is then passed up inside bell 

 jar through one of perforations in stopper. Seat stopper 

 firmly in mouth of bell jar. Stretch piece of sheet rubber over 



PIG. 106. Diagram of apparatus to demonstrate the action of the diaphragm. A, 

 in inspiration diaphragm flattened by contraction; B, in expiration diaphragm 

 relaxed and pushed upward by abdominal contents. Note changes in fullness of 

 lungs. 



larger end of bell jar and tie firmly in position. Press this 

 rubber membrane down on top of bowl and close free rubber 

 tube with pinchcock. 



a) To represent inspiration, lift bell jar from bowl, allowing 

 rubber membrane to flatten. 



b) To represent expiration, press membrane down over bowl. 



c) To represent effect of puncture of chest wall, remove 

 pinchcock from tube and lift jar from bowl. 



