Page 40 - Human anatomy COMPLETELY DONE1

Figure 27. Fallopian tube

During the period of embryonic development, about 40 thousand immature eggs
are laid in the body of a future woman, of which no more than 500 cells will reach
maturity during her entire reproductive age.
In a mature female body, about once a month, usually one egg in one of the two
ovaries is released from the follicle and enters the fallopian tube. A follicle is a bubble
in which an egg cell matures.
Follicle maturation occurs under the influence of a specific pituitary hormone.
The process of the egg leaving the follicle is called ovulation. Not fully mature
egg gets through the fringed funnel into the oviduct, where it moves to the uterus for 7
days, while its maturation is completed (figure 28).
In the ovary, the cavity of the burst follicle is gradually filled with cells
containing a fat-like substance of yellow color. The follicle turns into a yellow body –
a temporary gland of internal secretion. The follicles and the corpus luteum produce
female sex hormones. One of them is progesterone.
The hormone of the corpus luteum delays the maturation of the next follicle and

prepares the uterine mucosa for embryo acceptance.

Figure 28.
1 – menstruation, 2 – maturing follicle, 3 – graaf follicle, 4 – ovulation,
5 – yellow body, 6 – yellow body ceases to function

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