In human reproduction, the essential organs in which the germ-cells are kept segregated are
the gonads (sex-glands), ovaries in the female (Fig.10) and testes in the male.
The Women Organs
The ovaries, small almond-shaped organs, lie in the pelvis.
Each contains some half million primordial germ-cells.
These are dormant between birth and puberty.
Then until menopause (cessation of menstruation , occurring normally between
the ages of 45 to 50) one such cell matures once a month and passes into
the cavity of the uterus, where its subsequent history depends on
whether fertilization has occurred (if not, at is discharged within a few hours).
The Men Organs
The testis (Fig.11) consists of a mass of small tubes in which great numbers of
spermatozoa are constantly being produced.
They are conveyed to the seminal vesicles, from which they may be discharged through
the urethra in semen, a viscous liquid.
In coitus, semen is ejaculated through the penis into the upper end of the vagina,
bathing the cervix, one cc. of semen may contain several hundred million sperms,
which moves in a random manner, a few entering the uterus fewer still the uterine
(Fallopian) tube, where one spermatozoa may penetrate the layer of the cells which surround
an ovum and effect fertilization.
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