SECTION IX. 

 GENERAL PHYSIOLOGY. 



CHAPTER XL. 



PROPERTIES OF LIVING PROTOPLASM. 

 CHEMICAL CONSTITUENTS OP PROTOPLASM. 



In the broadest sense physiology is that science which deals 

 with the phenomena of living matter and attempts to explain these 

 phenomena in terms of physics and chemistry. To the majority 

 of people physiology means in reality "human" or at best "mam- 

 malian" physiology, i.e., a study of the functions of the human 

 body, or where this is not possible the functions of the dog or cat 

 are studied with the 'assumption that the physiology of these 

 mammals is comparable with our own. This is a perfectly natural 

 concept since we are primarily interested in ourselves, and are 

 interested in other living things only as they have some reference 

 to ourselves to be cultivated if they work for our good, to be 

 guarded against if harmful. Recently, however, it has been 

 demonstrated that light may be thrown on many problems in 

 human and mammalian physiology by a study of the life pro- 

 cesses in the more lowly forms of the animal world, and of the 

 plant world as well. To this study of the broader, more general 

 aspects of the functioning of living material in any form wherever 

 life exists has been applied the title of General Physiology. 



I. The properties of living protoplasm as shown in simple plant 

 animal cells. 



Materials: Spirogyra, Elodea, cells of onion epidermis, Para- 

 mecia, Amoebae ,Stentor, stamen hairs of Tradescantia. 



A. Examine the materials provided for the following points: 

 colour, consistency, optical nature, elasticity, viscosity and other 

 physical characteristics. Is protoplasm homogeneous? What is 

 the nature of the inclusions? What does the shape of the inclu- 

 sions tell one as regards the physical state of protoplasm? Crush 

 the cells or cut them in two. What happens to the protoplasm? 



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