100 Introductory Biology 



LIVING (ANIMATE) ORGANISMS 



NONLIVING (INANIMATE) 

 SUBSTANCES 



STRUCTURE AND ORGANIZATION 



All living protoplasm is a complex and 

 specific organization of structures 

 and parts which are coordinated so 

 as to function together as a unit, or 

 an organism. All living things are 

 composed of units, called cells, which 

 have nuclear materials, cytoplasm, 

 etc., each possessing distinct char- 

 acteristics and properties. The lat- 

 ter are constantly changing because 

 the chemical and physical constitu- 

 ents are highly organized in a dy- 

 namic system. 



Certain nonliving substances, such as 

 crystals, may have a definite molecu- 

 lar structure and organization typical 

 for each kind of crystal, but this or- 

 ganization is inert, static, and not dy- 

 namic. The various structures which 

 characterize each inanimate sub- 

 stance are rather simple in compari- 

 son with complex protoplasm, and 

 all nonliving substances arc without 

 cells. 



RESPIRATION AND WASTE ELIMINATION 



All living organisms respire, or ex- 

 change oxygen and carbon dioxide at 

 rather definite measurable rates. 

 These gases (oxygen for animals; 

 carbon dioxide for plants) are usu- 

 ally taken from the atmosphere. 

 During metabolism, there is respira- 

 tion and the production and elimina- 

 tion of wastes. In many living or- 

 ganisms the latter have rather specific 

 qualities which characterize the dif- 

 ferent kinds of living things. 



The exchange of gases is present in 

 certain inanimate substances, but it 

 is not quite the same kind of phe- 

 nomenon found in living organisms. 

 A nail may rust or oxidize (oxygen 

 added), or a motor may take in 

 oxygen and give off carbon dioxide, 

 or carbon monoxide, but these and 

 similar phenomena are different 

 from true respiration. 



MOVEMENT 



Dynamic movements usually result 

 from rather complex interactions of 

 physical and chemical forces within 

 the protoplasm. These independent, 

 autonomous movements seem to be 

 responses to stimuli with an expendi- 

 ture of energy rather than imposed 

 by external forces. They may be 

 rapid or slow, depending upon the 

 organism and the quantity and qual- 

 ity of stimuli. 



Certain inanimate things seem to dis- 

 play certain movements which may 

 seem to approximate those of living 

 organisms, although they are usually 

 of a simpler nature. Camphor par- 

 ticles in water may move and modify 

 their movements in response to cer- 

 tain external factors. Crystals of 

 certain types (salts, etc.) dissolve and 

 diffuse (move) in an aqueous en- 

 vironment. A drop of mercury in 

 water to which nitric acid is added 

 seems to display a type of movement 

 which somewhat resembles the "flow- 

 ing" movements of living protoplasm. 

 Brownian movements are displayed 

 by such things as particles of dyes 

 suspended in water etc. 



