ANIMAL BIOLOGY 



CHAPTER I 



THE PRINCIPLES OF BIOLOGY 



BIOLOGY (Greek, bios, life; logos, discourse) means the 

 science of life. It treats of animals and plants. That 

 branch of biology which treats of animals is called zoology 

 (Gr. zoon, animal ; logos, discourse). The biological 

 science of botany (Gr. botanc, plant or herb) treats of 

 plants. 



Living things are distinguished from the not living by a 

 series of processes, or changes (feeding, growth, develop- 

 ment, multiplication, etc.), which together constitute what 

 is called life. These processes are called functions. Both 

 plants and animals have certain parts called organs which 

 have each a definite work, or function; hence animals and 

 plants are said to be organized. For example, men and 

 most animals have a certain organ (the mouth) for taking 

 in nourishment; another (the food tube), for its digestion. 



Because of its organization, each animal or plant is said 

 to be an organism. Living things constitute the organic 

 kingdom. Things without life and not formed by life 

 constitute the inorganic, or mineral, kingdom. Mark I for 

 inorganic and O for organic after the proper words in this 

 list: granite, sugar, lumber, gold, shellac, sand, coal, paper, 

 glass, starch, copper, gelatine, cloth, air, potatoes, alcohol, 

 oil, clay. Which of these things are used for food by 

 animals ? Conclusion ? 



B i 



