FIBROUS, ELASTIC, AND ADIPOSE TISSUES 



81 



that hold the bones together at the joints. The tendons are also 



made of it. These attach muscles to the bones and are commonly 



called cords. In bending the 



wrist or stretching the neck, 



these cords are easily seen. 



When elastic fibers predom- 

 inate in connective tissue, it 



gives a yellowish color to the 



tissue and is known as elastic 



tissue. It is more elastic than 



fibrous tissue but not so 



strong. It is found between 



adjacent vertebrae, insuring 



elasticity to the vertebral 



column. It is also found in 



the walls of blood vessels. 



The adipose cells store excess supplies of fat. These cells com- 

 pose, to a large extent, the yellow marrow of bone. Deposits 



j4/ of fatty cells are in the 



;/; deeper layers of the skin 



and encase organs such as 

 the kidneys and heart. 

 When the fat is needed 

 by the body for metabo- 

 lism, certain enzymes in 

 the cell enter the vacuole 

 and digest the fat. 



In general, the cells of 

 connective tissue support 

 the organs and make the 

 framework of the body. 



Compare this photomicrograph of a cross section 

 of bone with the diagram shown on page 79. 



-tohite fibrous 

 connective- 



Droplets of oil enter certain cells. This oil in- 

 creases in volume by additional particles entering 

 the cells and crowding the protoplasmic contents of 

 the cell into a small mass. The cell becomes dis- The tOUghnCSS of tendons, 

 torted. The oil may be transformed to" fat. Masses of 

 these cells build the fat or adipose tissue of the body. 



the extensile character of 



