348 



ANATOMY AND PHYSIOLOGY 



When the uterus receives an impregnated ovum its function is 

 exercised in protecting and nourishing the growing embryo until 

 it becomes a fully developed fetus. The mucous membrane 

 thickens to form a bed for the embryo, and becomes a part of the 

 placenta or " afterbirth." The muscle fibers grow in size and 



number and the weight 

 increases from the origi- 

 nal ounce and a half to 

 one or more pounds. 



The function of the 

 uterus is concluded with 

 the expulsion of the 

 fetus and placenta. It 

 then contracts rapidly, 

 and the process of invo- 

 lution softens and dis- 

 charges the remains of 

 tissue which is no longer 



FIG. 225. THE UTERUS. needed. (See p. 358, 



Showing cavity and attachment of vagina. 7 7 \ 



Morris.} lochta.) 



Position. Thefundus of the uterus is normally inclined somewhat forward, while 

 the os externum looks downward and backward. If the fundus turns too far 

 forward this is anteversion; if it inclines backward, retr aversion. 



A bend may exist where the neck joins the body. This is flexion. When the 

 body is bent forward, this is anteflexion; when backward, retroflexion. 



THE UTERINE TUBES (FALLOPIAN TUBES) 



The uterine tubes (Fallopian tubes) two in number (Fig. 224), 

 extend outward from the upper angles of the uterus; they have a 

 fibre-muscular structure and are lined with mucous membrane. 

 Each tube is about four inches long. At the beginning it is only 

 large enough to allow the passage of a small bristle, but it becomes 

 larger toward the end, expanding into a trumpet-shaped extremity 

 called the infundibulum, which is fringed or fimbriated, and which 

 is connected with the ovary below by a slender band (or fimbria). 



The function of the uterine tube is to convey the ovum from 

 the ovary to the cavity of the uterus. 



THE OVARIES 



The ovaries, two in number, lie on either side of the body of 

 the uterus, each one being connected to it by a short cord called 



