The human female reproductive
systems function is for human reproduction which is made up of internal and
external sex organs. The human female reproductive system includes the breasts,
vagina, vulva, fallopian tubes, ovaries, uterus, and mammary glands. Each of
these organs play a unique part in the production and transportation of gametes
and the production of the sex hormones. The process that the human female
reproductive system undergoes to carry out the role in the process of pregnancy
and birth is sexual maturation.
start with the ovaries. The ovaries are a pair of small glands the size and
shape of grapes that are located on the left and right sides of the pelvic body
cavity lateral to the superior potion of the uterus (The ovaries are
highlighted in the image above). The ovaries have three main functions. The
first function is that they shelter and protect the eggs until they are ready
for use. Second, the ovaries produce female sex hormones called estrogen and progesterone.
It also produces lesser hormones called Relaxin and Inhibin. There are three
different types of estrogen. They are called estrone, estriol, and estradiol.
Estrogen are hormones that are important for sexual reproductive development.
It controls the development of the mammary glands and uterus during puberty. At
the onset of puberty, it plays a role in the development of hips, breasts,
armpit hair, and pubic hair. Estrogen also works with the menstrual cycle by
regulating it by controlling the uterine lining during the first part of the
cycle. Estrogen will work with progesterone to stop ovulation during pregnancy
and progesterone acts on the uterus during pregnancy to allow the embryo to
implant and develop in the womb. They play two key roles in the female
reproductive system by acting as gonads and glands. Inhibin stops the pituitary
gland from making hormones and Relaxin loosens the pelvic ligaments, so they
can stretch during labor. The third major function of the ovaries is that it
releases one egg each menstrual cycle which is called ovulation. A female can
only become pregnant if a sperm fertilizes that egg.
let’s get to the uterus highlighted above. The uterus is a hollow, muscular,
pear-shaped organ located between the bladder and the rectum in the pelvic
area. It provides structural integrity and support to the bowel, pelvic bones,
bladder, and organs as well. The lower end of the uterus, the cervix, opens
into the vagina (which I will speak about later), and the other end, the fundus,
is connected to the fallopian tubes (which I will talk about next). The nerves
and networks of blood vessels of the uterus direct blood flow to the external
genitalia for sexual response. It is needed for the uterine orgasm to happen.
The uterus has three layers, the inner lining (the endometrium), the middle
muscular layer (the myometrium), and the outer layer (the perimetrium). The main
purpose of the uterus is to nourish a fetus before birth. The ovaries release eggs
(as I said before) that travel via the fallopian tubes to the uterus. If the
eggs are fertilized, then they will bind to the wall of the uterus and the
fetus will start to develop. The
perimetrium or serosa is the outer layer that forms the skin of the uterus. It
protects the uterus from friction by forming a layer of simple squamous epithelium
along its surface and secreting fluids to lubricate the surface. The myometrium
is the middle layer of the uterus which contains many layers of visceral muscle
tissue. The myometrium layer helps during labor by pushing the baby out of the
uterus. The endometrium layer borders the hollow lumen of the uterus. It is the
most active layer and responds to cyclic ovarian hormone changes. It is highly
specialized and is essential to menstrual and reproductive function. Around
ovulation time the uterus builds a thick layer of vascular endometrial tissue
in preparation to receive a fertilized egg, or zygote. If the egg is not
fertilized it will pass through the uterus and trigger blood vessels of the endometrium
to atrophy and the uterine lining to be shed. This is known as menstruation and
occurs approximately every 28 days. The uterus of a child is small until puberty,
where it grows fast to its adult size and shape and then after menopause when
the female can’t have children anymore, it becomes smaller.
Next up is the fallopian tubes or
uterine tubes. They are a pair of muscular tubes that extend from the left and
right superior corners of the uterus to the edge of the ovaries as shown above.
The fallopian tube carries an egg from the ovary to the uterus. The ampulla, a
section of the fallopian tubes is where an egg is fertilized by a man’s sperm.
The fertilized egg moves to the uterus where it develops until birth. Each
fallopian tube is around 10cm in length and 1cm in diameter and is placed within
the mesosalpinx. The fallopian tube has 3 parts. The first part is called the
isthmus, which is a small region, around 2cm long that connects the ampulla and
the infundibulum to the uterus. The second is the ampulla, which is the central
portion of the fallopian tube leading from the infundibulum. The third is the
infundibulum which is the farthest from the uterus. The infundibulum catches
and channels the released eggs. The intramural, the final region of the fallopian
tube, is located on the top portion of the uterus, is where fertilized eggs
normally attach and develop. The fallopian tubes have small hair-like
projections on the cells of the lining called the cilia. They are essential to
the movement of the egg through the tube into the uterus. The mucous membrane
that lines the fallopian tube gives off secretions that help move the sperm and
egg to keep them alive. The secretions are mostly calcium, chloride, sodium,
proteins, sugar(glucose), lactic acid, and bicarbonates. The bicarbonates and
lactic acid are most important to the sperms use of oxygen, which also help
develop the egg once fertilized.