[chambers] 



MICRODISSECTION OF CELLS 



43 



shaped bodies, the mitochondria, imbedded in the cytoplasm are 

 ver)^ prominent. The cytoplasm is very extensile and exhibits a 

 certain amount of rigidity throughout its substance. It can be pulled 

 out into long, viscous threads and the imbedded mitchondria are 

 drawn in the direction of the pull. 



CI amp for 

 NçGOle 



Front and bûcK 

 move»Tien 



6ide 1o side 

 move ment" 



Figure 1. Barber's Three-Movement Pipette Holder, Glass Needle 

 and Moist Chamber arranged to illustrate method of dissecting 

 cells in a hanging drop under the highest magnification of the 

 microscope. (Substage of microscope omitted in drawing.) 



On exerting a pull on the cytoplasm in a direction away from the 

 nucleus, a triangular space appears in front of the nucleus and persists 

 for a few minutes. This is due to the viscosity of the cytoplasm which 

 prevents an even flow of material around the nucleus as should occur 

 if the cytoplasm were liquid. 



There is a limit to the amount of mechanical injury which the 

 cytoplasm can bear without completely changing its normal prop- 

 erties. When this limit is passed the viscid plasma sets into a 

 coagulated, non-viscous mass which may be broken into non-glutinous 

 pieces. 



