64 



PHYSIOLOGY 



It is important that food should be properly chewed. 

 In order that the enzymes may digest food they must 

 come directly in contact with food particles. If large 

 pieces are swallowed, the enzymes come in contact with 



Fig. 42.— Section of skin highly magnified showing sweat glands. Ep. y Epidermis; 

 D., Dermis; Sub. T., Subcutaneous tissue ; a, Shaft of hair ; ft. Horny layer of 

 skin ; c, Duct of sweat gland ; d, Papilla ; e, Capillaries of papillae ; /, Sebaceous 

 glands; g, Connective tissue; h, Erector muscle of hair; i, Artery; k, Hair fol- 

 licle; I, Coil of sweat gland ; m, Artery to sweat gland; n, Papilla of hair; o, 

 Connective tissue; p, Fat. (From Fitz.) 



the surface only. Only the outer surface will then be 

 digested. Undigested masses are thrown into the intes- 

 tine, fermentation takes place and poisonous substances 

 are absorbed. Food should be chewed until it no longer 

 has a specific taste and until it is a homogeneous mass. 

 Chewing keeps the teeth in good condition by pro- 

 viding them with exercise. Most dentists say that a 



