CHAPTER X 

 MUCOUS MEMBRANES GLANDS 



The histologic structures which are necessary for the formation of 

 a secretion include an epithelial surface, and a tunica propria of con- 

 nective tissue which supports the requisite blood and lymphatic vessels 

 and the controlling nerve supply. These structures may either form 

 smooth membranous surfaces or apparent epithelial imaginations. The 

 former are found on the surface of the mucous membranes, the latter 

 are the secreting glands. 



MUCOUS MEMBRANES 



The mucous membranes may be said to include all those secreting 

 surfaces which are directly or indirectly connected with the surface of 

 the body, hence their epithelial clothing is continuous with that of the 

 skin. The mucous membranes form the lining coat of the respiratory 

 and alimentary systems, together with the ducts of their secreting glands ; 

 in the nose this membrane is continuous through the tear ducts with 

 the conjunctiva of the eye and through the auditory (Eustachian) tubes 

 with the lining membrane of the middle ear. The broad expanse thus 

 formed is known as the gastropneumonic mucous membrane. A second 

 membranous sheet, the ge nit o-uri nary mucous membrane, clothes the 

 organs of the genital and urinary systems ; it thus forms the lining mem- 

 brane of the vagina, uterus, and Fallopian tubes, of the urethra, bladder, 

 ureters and pelvis of the kidney, of the ducts and tubules of the prostate 

 gland, the testis, and the smaller secreting glands which are connected 

 with the genital system. 



A mucous membrane consists of a superficial layer of epithelium 

 of varying type, which rests upon a basement membrane (membraua 

 propria) and is in turn supported by an investment of connective tissue, 

 the tunica propria, or corium. The tunica propria is richly supplied 

 with small blood-vessels and lymphatics; its nerve fibrils are not only 

 distributed to the walls of the blood-vessels but in many cases send ter- 



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