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SECONDARY SEX ORGANS
a. Uterine Tubes (Fallopian Tubes, Oviducts). Extending to either side of
the uterus are two muscular tubes, which open at the outer ends like fringed trumpets.
The fringe-like appendages encircle the ovaries. At their medial ends, the uterine tubes
open into the uterus. The function of the uterine tubes is to pick up the ovum when
released from the ovary and hold it UNTIL one of the following happens:
(1) Fertilization. Then it is fertilized. After fertilization, the initial stages of
embryo development take place. The developing embryo is eventually moved into the
uterus.
(2) Death of Ovum. The nutrient stored within the ovum is used up, and
the ovum dies. This may take 3-5 days.
b. Uterus. The uterus is the site where all but the first few days of embryo
development takes place. After 8 weeks of embryonic development, it is known as the
fetus.
(1) Main subdivisions. The uterus is shaped like a pear, with the stem
(cervix) facing downward and toward the rear. The fundus is the portion of the uterus
above the openings of the uterine tubes. The main part, or body, is the portion between
the cervix and the fundus. The uterus usually leans forward with the body slightly
curved as it passes over the top of the urinary bladder. The cervix opens into the upper
end of the vagina.
(2) Wall structure. The inner lining of the uterus is called the
endometrium. Made up of epithelium, it is well supplied with blood vessels and glands.
The muscular wall of the uterus is called the myometrium. In the body of the uterus, the
muscular tissue is in a double spiral arrangement. In the cervix, it is in a circular
arrangement.
(3) Age differences. The uterus of an infant female is undeveloped.
During puberty the uterus develops. The uterus of an adult is fully developed. The
uterus of an old woman is reduced in size and nonfunctional.
c. Vagina. The vagina is a tubular canal connecting the cervix of the uterus
with the outside. It serves as a birth canal and as an organ of copulation. It is capable
of stretching during childbirth. The low opening of the vagina may be partially closed by
a thin membrane known as the hymen.
d. External Genitalia. Other terms for the external genitals of the human
female are vulva and pudendum. Included are the:
(1) Mons pubis. The mons pubis is a mound of fat tissue covered with
skin and hair in front of the symphysis pubis (the joint of the pubic bones).
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