Life and Health 



THE PRINCIPAL TISSUES OF THE BODY 



21. The Chief Tissues classified. The chief tissues which 

 form the organs of the body may be classified as follows : 



I. Nervous Tissues. 



II. Muscular Tissues. 



III. Epithelial Tissues. 



IV. Connective Tissues 



1. White and Elastic, Fibrous. 



2. Areolar or Cellular. 



3. Adipose or Fat. 



4. Adenoid or Retiform. 



5. Cartilage. 



6. Osseous or Bone. 



The most important tissues, the nervous and muscular, 

 the " master tissues," - are those by which the active life of 

 the individual is carried on. These 

 will be described in later chapters. 



The remaining chief tissues epi- 

 thelial and connective will now be 

 briefly explained. 



The osseous tissue, or bone, will be 

 described in Chapter II. 



THE EPITHELIAL TISSUES 



22. Epithelium. Cells are associ- 

 ated and combined in many ways to 

 form tissues. The distinctive charac- 

 ter of every tissue depends on its 

 structure, its mode of union, and the 

 FIG. 5. Cross-Section of vital properties of its elements. 



Squamous Epithelium Qne Q the simplest Q f the tissues 



from the (Esophagus. . ,. . . 



is called epithelium, or surface-limiting 

 tissue, and the cells are known as epithelial cells. 



