20 VETERIN,\RV PATHOLOGY. 



THE CELL. 



ANATOMIC. 

 Structuie. 



Body. 



Nucleus. 



Cciitrosomc. 



Membrane. 

 Shape. 

 Size. 

 PHYSIOLOGIC. 

 Gmvth. 

 Reproduction. 

 Motion. 

 Metabolism. 



Aiiabolisiii. 



Katabolisni. 

 IRRITABILITY. 



Structurally, an animal body is composed of definitely ar- 

 ranged parts, called organs. An organ is a portion of the 1)ody 

 having a jiarticular function and is, structurally, a tissue-complex 

 in which each tissue has a certain definite proportion and relation. 

 A tissue is composed of like or similar cells with mure or less 

 intercellular substance interposed. The intercellular substance is 

 usuall}^ a product of the cells. A cell has been defined as a 

 microscopic mass of protoplasm containing sufficient individ- 

 uality to possess a life history. 



The function of an animal body is the sum total of the corre- 

 lated functions of its component tissues. The function (jf a 

 tissue is the sum total of the function of its cells. Thiis a cell 

 represents the anatomical or structural unit and the physiologic 

 or functional unit of all animal bodies. 



In ancient times disease was thought to be the result of 

 the entrance into the bodv of some "evil s])irit," and the symp- 

 toms presented during disease was evidence of the struggle 

 beween the body and the "evil spirit." During the middle ages, 

 Hippocrates, "The Father of Aledicine," established the Hippo- 

 cratic Theory of disease. Hippocrates taught, 1st, that the l)ody 

 was composed of four humors, viz., blood, phlegm, yellow bile 

 and black bile ; 2nd, that health consisted of the proper balance 

 of the humors; and 3d, that disturbed proportions <;>f the hum- 

 ors resulted in disease. 



Modern pathology is based upon the knowledge of cell activi- 

 ties. Virchow was the father of cellular pathology. He first 

 taught the cellular theory to students of pathology and he first 

 advocated it in published articles. Cellular physiology was really 

 an outgrowth of cellular pathology. A knowledge of cells is 



