Download Female Reproductive System

Unit Four
“Female Reproductive System”
Female Reproductive System
• Primary Sex Organs – Paired Ovaries
• Secondary Sex/Accessory Organs –
include the Uterus, Fallopian Tubes,
Vagina, Cervix, and the Endometrium
Female Reproductive System
• Primary Sex Organs
– The Paired Ovaries are oval shaped
structures that contain the eggs used in
reproduction
– They also produce the female sex hormones,
Estrogen and Progesterone, which are
needed for the successful release of ova
Female Reproductive System
– Each Ovary is located within the abdominal
cavity just above either pelvic bone
– Several ligaments hold the ovaries in place by
attaching to the Uterine Tubes, Uterus, and
the Pelvic Wall
– The interior of Ovary is composed of two
sections:
• Outer Cortex – contains many follicles at various
stages of maturation
• Inner Medulla – area where blood vessels and
nerves enter the ovary
Female Reproductive System
• Immature ova, called Oocytes, are contained
within larger structures called Follicles
• A female is born with as many as 2 million
follicles but of that large number, only
approximately 400 will mature
• As stated previously, females are born
containing all the follicles they will every
possess. Therefore, the older the woman is
when she conceives, the higher the likelihood for
genetic abnormalities in the baby. The ova have
been in storage for an extended period of time.
Oogenesis
• Oogenesis is the process by which
mature ova are produced via meiosis
• As with Spermatogenesis, Oogenesis
begins with a Primary Oocyte that
proceeds through Meiosis I
• Once the Primary Oocyte has
successfully completed Meiosis I, it is now
a Secondary Oocyte that will become the
mature ova
Oogenesis
• 1. Recall the Follicle contains the developing
ovum
• 2. As the Follicle matures, Primary Oocyte
divides, producing two cells
• 3. Of the two cells, one is the Secondary
Oocyte, and the other is a Polar Body
• 4. During Ovulation, the Follicle bursts, releasing
the Secondary Oocyte
• 5. The Secondary Oocyte enters the Fallopian
Tube where it may successfully unite with a
Sperm
Oogenesis
• The Ovaries alternate monthly in
producing a mature Follicle that will burst
releasing a Secondary Oocyte
• The number of Secondary Oocytes
produced by a female in her lifetime is tiny
compared to the number of Sperm a male
produces during his lifetime
Female Reproductive System
Female Internal Accessory Organs
• Fallopian/Uterine Tubes
– long tubular structures; allows for passage of the
fertilized secondary oocyte (blastomere) from the
ovaries to the uterus via the back and forth action of
cilia (microscopic hairs)
• It takes several days for the blastomere, now
becoming the Blastocyst to enter the Uterus, and
then become embedded in the Uterine lining
• Ectopic Pregnancy – a Blastocyst that
becomes embedded in the wall of the Fallopian
Tubes; does not result in a viable fetus
Female Internal Accessory Organs
• Uterus
– It is found adjacent to the Urinary Bladder,
and is centrally located in the lower abdominal
cavity of a female
– It is a thick walled muscle that has the shape
of an inverted pear
Female Internal Accessory Organs
• Uterus continued
– Three layers of the Uterus: Outer, Middle, and
Inner Layers
• Outer – part of covering for pelvic cavity
• Middle – very muscular and contracts
(“contractions”) during childbirth in response to
hormone oxytocin
• Inner – “Endometrium” – has two parts, one
permanent, and one shed monthly if fertilization
does not occur (“menstrual period”)
Female Internal Accessory Organs
• Uterus continued
– The Uterus is divided into three vertical
sections:
• 1. Fundus – top of the inverted “pear”
• 2. Body – the majority of the “pear”
• 3. Cervix – narrow end of the uterus that connects
to the vagina
*** Cervical Cancer is a common form of cancer for
women, and can be detected in its early stages by
Pap Smear; removal of the uterus may be required
Female Internal Accessory Organs
• Vagina
– It is a fibromuscular tube approximately 9 cm long
that is angled
– The Vagina is in front of the Rectum but behind the
Urinary Bladder
– The Vagina, as it is a muscle, is able to extend to
allow for childbirth and sexual intercourse
– The opening to the Vagina is initially enclosed by
tissue called the Hymen; it is usually ruptured by
sexual intercourse but can also break due to other
physical activities
Female Internal Accessory Organs
External Genitals
• There are four external genitals of the female:
– 1. Labia Majora – large folds of skin
– 2. Labia Minora – small folds of skin within the
Labia Majora
– 3. Glans Clitoris – Sexually Sensitive/Pleasure
Organ
– 4. Vestibular Glands – portion of skin that contains
the openings to the urethra and the vagina; in females
the urethra and the vagina do not converge which is
dissimilar to the convergence of the ejaculatory duct
and the urethra in males
Female Reproductive Cycle
• Menstrual Cycle = “Period”
– Puberty (11 to 13 years of age) signals the onset of
the Menstrual Cycle in females
– Initially, a post pubescent female’s period is sporadic,
but as she ages, it becomes more frequent and
consistent
– Within a few years after a female’s first period, her
cycle will become regulated due to the presence of
hormones, with her period lasting 7 days, and the
time between each period lasting about 21 days = 28
day cycle
– Hormones such as Estrogen and Progesterone are
extremely important in regulating a female’s
reproductive cycle
Female Reproductive Cycle
Female Reproductive Cycle
• If fertilization and subsequent implantation occurs, HCG
(Human Chorionic Gonadotropin) communicates
chemically with Corpus Luteum (remains of follicle) to
produce progesterone until the Placenta begins its own
production of Estrogen and Progesterone
• Once the Placenta begins producing these hormones,
the Pituitary Gland in the brain no longer sends
messages to the ovary to produce more follicles until the
pregnancy is complete
• These hormones also maintain the Endometrium
throughout the pregnancy
Female Reproductive Cycle
• Menopause
– The cessation of the female reproductive cycle
– The hormones no longer are produced by the
Pituitary Gland to maintain the activity of the ovaries,
and hence, there is no more potential for childbearing
– Usually occurs between the ages of 45 and 55
– Symptoms are: hot flashes, dizziness, headaches,
insomnia, sleepiness, and depression
Female Reproductive System
Overview
• https://www.youtube.com/watch?v=2_owp
8kNMus
• https://www.youtube.com/watch?v=a8fgmzEYjQ