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The Reproductive System. Female. Reproductive role. Produce the female gamete (ova) Nurture and protect a developing fetus during 9 months of pregnancy Primary reproductive organ: Ovaries Produce exocrine product: Ova Produce endocrine product: estrogen and progesterone. Ovaries.
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The Reproductive System Female
Reproductive role • Produce the female gamete (ova) • Nurture and protect a developing fetus during 9 months of pregnancy • Primary reproductive organ: Ovaries • Produce exocrine product: Ova • Produce endocrine product: estrogen and progesterone
Ovaries • The paired ovaries are the size and shape of almonds • Ovarian follicles: tiny saclike structures within the ovaries • Each follicle consists of an immature egg called an oocyte • Oocyte is surrounded by one or more layers of very different cells called follicle cells
Ovulation • As a developing egg within a follicle begins to mature: • The follicle enlarges and develops a fluid-filled central region called an antrum • At this stage, ovulation happens: the follicle is mature and the developing egg is ready to be ejected from the ovary • After ovulation, the ruptured follicle is transformed into a very different looking structure called a corpus luteum, which eventually degenerates
Duct System • duct system: • The uterine (fallopian)tubes • Uterus • Cervix • Vagina
Fallopian tubes • Form the initial part of the duct system • Receive the ovulated oocyte and provide a site where fertilization can occur • Each of the fallopian tubes is about 10 cm long • There is little or no actual contact between the fallopian tubes and the ovaries
Fallopian tubes • The distal end of each fallopian tube is expanded and has fingerlike projections called fimbriae: • As an oocyte is expelled from an ovary during ovulation, the waving fimbriae create fluid currents that carries oocyte into the uterus • The oocyte is carried toward the uterus by a combination of peristalsis and rhythmic beating of cilia
Fertilization • The usual site of fertilization is the fallopian tube • To reach the oocyte, sperm must swim upward through the vagina and uterus to reach the fallopian tube
Uterus • It is located in the pelvis between the urinary bladder and rectum • Function: to receive, retain, and nourish a fertilized egg • No pregnancy: It is about the size and shape of a pear
Uterus • The major portion of the uterus is referred to as the body • Its superior rounded region above the entrance of the fallopian tube is the fundus • Its narrow outlet which protrudes into the vagina below is the cervix
Uterus • The wall of the uterus is thick and composed of 3 layers: • endometrium: inner layer • Myometrium: bulky middle muscle layer • Epimetrium: outermost layer
Endometrium • If fertilization occurs: • The fertilized egg implant itself into the endometrium of the uterus and resides there for the rest of its development • When a woman is not pregnant: • The endometrial lining is brushed off periodically, usually about every 28 days, in response to changes in the levels of ovarian hormones in the blood (menses)
Myometrium • Myometrium: • It is composed of interlacing bundles of smooth muscle • The myometrium plays an active role during the delivery of a baby
Vagina • It is a thin-walled tube 8 to 10 cm long • It lies between the bladder and rectum and extends from the cervix to the body exterior • The distal end of the vagina is partially closed by a thin fold of the mucosa called the hymen: • The hymen is very vascular and tends to bleed when it is ruptured
External Genitalia • Includes: • Mons pubis • Labia • Clitoris • Urethra • Vaginal orifice • Greater vestibular glands
Vestibular glands • A pair of mucus-producing glands • Their secretion lubricates the distal end of the vagina
Clitoris • A small protruding structure that corresponds to the male penis • Like the penis, it is hooded by a prepuce and is composed of sensitive erectile tissue • The clitoris differs from the penis in that it lacks reproductive duct
Perineum • The diamond shaped region between the posterior end of the labial folds and the anterior end of the anus is the perineum