HUMAN REPRODUCTION 



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are small, ovoid or almond-shaped bodies situated low in the abdomen 

 and suspended in position by ligaments attached to the side walls of the 

 pelvis and to the uterus. Like the uterus and the other abdominal organs, 

 the ovary projects into the abdominal cavity and is covered by the 

 peritoneum, which envelops the organ, and by its folds forms the support- 

 ing ligaments. 



Within the ovary, the developing germ cells are surrounded by special 

 soma or body cells that nourish them while they grow and mature. These 

 accessory cells form a spherical structure imbedded in the ovary, known 

 as an ovarian follicle. As the follicle enlarges, a split develops along one 

 side between its inner and outer cell layers, and the space thus formed 



ovary 



uterus 



large intestine 



vagina 



anus 



labium major 

 Fig. 16.2. The female reproductive system. 



gradually fills with lymph and increases in size. When the egg is finally 

 mature and ready to leave the ovary, it lies, surrounded by a layer of 

 follicle cells, floating in the cavity of the much enlarged follicle. The latter 

 has in the meanwhile pushed out to the surface of the ovary, just beneath 

 the peritoneum that lines the peritoneal (or coelomic) cavity. The ovary 

 has no duct for the discharge of eggs. Instead, the eggs are freed by a 

 peculiar process called ovulation, which consists in rupture of the wall 

 of the follicle and the overlying peritoneum and discharge of the follicular 

 fluid and the egg into the peritoneal cavity. 



Actually the egg does not ordinarily escape into this cavity but is 

 discharged into or is at once picked up by the open end of the oviduct. 

 The oviducts are a pair of tubes extending from the upper portion of the 

 uterus to the vicinity of the two ovaries. There they end in enlarged, 



