Homogenes, iogenes [from lat. ovum (gr. Bon), the egg and the Greek. genesis - the origin, development] process of origin and development of the female reproductive cells, culminating in the formation of a Mature, able to fertilize the eggs.
Placental mammals, including humans, egg cells negligible amount develop from germinal epithelium surrounding the ovary. In homogenize there are three zones of development of germ cells - reproduction, growth and maturation.
Ovary placental mammals passes bisexual phase. In emerging ovary clearly expressed two generations of vrastani germinal epithelium into the thickness of the ovary. The first generation of cellular fibers "male type" with the development of ovarian cancer is reduced. Second generation cellular vrastani of the germinal epithelium, also called Pflugerville bags and cellular fibers Waldeyer becomes producing part of the emerging of the ovary.
Primary germ cells, or archovogonium, formed from cells Zacatecoluca epithelium. After repeated division they begin to grow into a zone of growth. At the beginning of the growth area of nuclear structure of the oocyte detects characteristic change - the so-called stage of Winiwarter representing the training divisions of maturation. Winiwarter (N. Winiwarter) described a stage bouquet, or synapsis: nuclear thread is broken into separate arch - chromosome (see), the ends of which are directed to a specific location of the nuclear envelope. Gregoire (V. Gregoire) interpreted the phenomenon synapsis as chromosome pairing. The essence of synapsis that when one of the two divisions maturation occurs longitudinal splitting of chromosomes (see Meiosis). The result is a Mature egg (see) is half the number of chromosomes. In this regard, Mature sex cell, unlike immature, has half of inherited traits.
It is this fact underlies the participation of so-called sex chromosomes (X and Y chromosomes) in sex determination (see) and in the inheritance of characteristics associated with sex, as well as defects in case of abnormal combination of sex chromosomes (XXX for women, XXY - for men) and others (see Heredity, Hereditary diseases). The same happens when you inherit physical signs of each of the parents.
For placental mammals and humans is a characteristic phenomenon of atresia of the follicle, accompanied by their death. In case of death of a Mature, large follicle this is known Fiziol. value: follicular epithelium is dissolved and the remaining cells of the inner layer of the shell dying follicle strongly divided and fill the cavity of the follicle, turning in an endocrine gland of the ovary. From the endocrine activity of these glands depends on the development of secondary sexual characteristics women.