GENERAL PROPERTIES OF THE ECTOPLASM 



organism is by means of ectoplasmic processes formed by 

 originally ectoplasm-rich cells and by chemicals furnished 

 by originally ectoplasm-rich cells. 



Now the integration of cell with cell — the simplest mode 

 of integration — is by means of the ectoplasm. Thus it is 

 evident that all forms of integration in the complex organ- 

 ism are in the last analysis ectoplasmic. 



Contraction is like conduction a fundamental property 

 of the living cell. The lowest forms of animal and plant 

 life have capacity for contractility either permanently or 

 at some time or other in their life-history. All the cells 

 of a highly organized multicellular organism possess it in 

 some degree. But this endowment may be reduced to such 

 a low point that it is almost extinguished. With evolu- 

 tion animals developed cells which were set apart as con- 

 tractile tissues. These are the muscle cells in which 

 this fundamental property of living substance is highly 

 emphasized. Muscle cells are also characterized by having 

 great length. The smooth muscle fibre is thicker than 

 either type of the striated muscle. It is also the least 

 responsive and shows the longest reaction-time. Theories 

 of muscle-contraction that have the widest acceptance 

 explain it as a surface-phenomenon. It is certainly true 

 that contractile tissues have relatively large surface area. 

 Their elasticity is undoubtedly a function of the surface — 

 as in the case of egg-cells. 



The life-process of a cell is the sum and interaction of its 

 manifold activities. The phenomena which together inhere 

 in the state of being alive reveal themselves as activities of 

 the protoplasm. No protoplasm exists without them. 

 For respiration, conduction and contraction, the foregoing 

 presentation offers proof that they are in particular mani- 

 festations of ectoplasmic activity. That nutrition is like- 

 wise bound up with the ectoplasm will become evident in 

 the next chapter. 



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