1 6 Life and Health 



THE CONNECTIVE TISSUES 



24. Connective Tissues. v The connective tissues serve 

 to unite and bind together the different organs and tissues. 

 Made up of fibers and cells, they form a sort of flexible 

 framework of the body. They so pervade every portion 

 of it that if all the other tissues were removed, we should 

 still have a complete representation of the bodily shape in 

 every part. 



X In brief, the connective tissues may be said to serve as 

 packing, binding, and supporting structures. This name 

 includes certain tissues which to all outward appearance 

 vary greatly, but which are properly grouped together. 



All these tissues consist of a ground-substance or matrix, 

 cells, and fibers. 



The ground-substance is best seen in hyaline cartilage, 

 where it has a glossy appearance. In bone it is infiltrated 

 with the salts which give to the osseous tissue its hardness 

 and make it seem so unlike other tissues. 



Experiment i. To examine squamous epithelium. With an ivory 

 paper-knife gently scrape the back of the tongue or the inside of the 

 lips or cheek ; place a tiny portion of the substance thus obtained 

 upon a glass slide ; cover it with a thin cover-glass, and if necessary 

 add a drop of water. Examine with the microscope, and the irregu- 

 larly formed epithelial cells will be seen. 



Experiment 2. To examine ciliated epithelium. Open a frog's 

 mouth, and with the back of a knife-blade gently scrape a little of 

 the membrane from the roof of the mouth. Transfer to a glass slide, 

 add a drop of salt solution, and place over it a cover-glass with a hair 

 underneath to prevent pressure upon the cells. Examine with a micro- 

 scope under a high power. The cilia move very rapidly when quite 

 fresh, and are therefore not easily seen. 



