36/37. Female Reproductive System Flashcards
Female external genitalia outside of vestibule
Also called vulva
Mons pubis - fatty, round pad on top of pubic symphysis
Labia majora - outer skin folds
Labia minors- inner skin folds, enclose a space called the vestibule
Female external genitalia within the vestibule
Vaginal orifice- external opening of the vagina that is partly covered by hymen, which is vascularized
External urethral orifice- anterior to vaginal orifice
Greater vestibular glands- lateral to vaginal orifice that secrete lubricating mucus into vagina during arousal
Clitoris- anterior to the vestibule, has hood called prepuce, primary sensory structure
Erectile tissues of the female
Clitoris is composed of paired corpora cavernosa
- has body and glands
- continues posteriorly as crura along inferior pubic ramus
Bulb of the vestibule is the erectile tissue on either side of the vaginal orifice
Erectile tissue become engorged with blood during stimulation
Muscles of female external genitalia
Bulbospongiosus muscle- sheet of muscles covering over bulb of vestibule
Ischiocavernosus muscle- sheet of muscle covering each crud of clitoris
Maintain erection of clitoris and emptying of greater vestibular glands
Innervation to external genitalia and pelvic structures
Inferior hypogastric plexus- parasympathetic and sympathetic innervation
Pudendal nerve- from sacral spinal region, gives rides to dorsal nerve of the clitoris giving sensation
Pelvic structures
Bladder sits behind pubic bone
Vagina and uterus between bladder and rectum
Uterus arches anteriorly
Uterine (fallopian) tube located anterior to ovary
Characteristics of the vagina
Thin walled canal leading from external environment to uterus
Lining is stratified squamous epithelium
Fornix is circular area surrounding cervix
Characteristics of the uterus
Hollow organ where embryo and fetus develop
Fundus-dome shaped top part
Body- main central part
Cervix- inferior donut shaped projector into vaginal canal
Layers of the uterine wall
Perimetrium
Myometrium
Endometrium
Characteristics of perimetrium
Outer serous membrane (peritoneum)
Characteristics of myometrium
Thick muscular layer
Produces contractions during childbirth
Characteristics of endometrium
Mucosal lining of uterine cavity
Simple columnar epithelium with CT
Highly vascularized
Function layer is thick inner layer that sheds during menstruation
Basal layer is thinner, doesn’t shed, and forms new functional layer
What is endometriosis
Painful condition in which endometrial tissue is found outside of uterus
Possibly due to reflux of menstrual fluid spreading endometrial cells beyond uterus
Tissue builds up and breaks down as normal (blood accumulates and has nowhere to go, can form cysts and scar tissue)
Occurs in 10% of women
Can cause infertility
What is the adnexa and its structures
3 structures that hang from the uterus
Ovary and ovarian ligament
Uterine (fallopian) tube
Round ligament
Characteristics of ovary and ovarian ligament
Ovaries are primary sex organ (gonad)
Produce gametes (oocytes)
Characteristics of uterine (fallopian) tubes
Transports oocytes from ovaries to uterine cavity
Fimbriae are finger like projections that draw oocyte into tube during ovulation
Site of fertilization of oocyte by sperm
Characteristics of round ligament
Travels anteriorly through inguinal canal on each side and attach to skin
Positional support for uterus
Characteristics of the broad ligament
Draping of peritoneum over the uterus and adnexa
Has different parts
Blood supply to ovaries
Ovarian (gonadal) artery originates from abdominal aorta and descends to supply blood to the ovaries
Ovarian (gonadal) vein merges with left renal vein on left side and IVC on right side
Stay inside pelvis
Blood supply to pelvic structures
Internal iliac artery gives off many branches to supply blood
Vesical artery - bladder
Uterine artery - uterus
Vaginal artery - vagina
Each have corresponding veins that drain to the IVC
Function of ovaries
Produce oocytes in cortex via oogenesis
Produce estrogen and progesterone
Characteristics of menstrual cycle
Approximately monthly hormone-induced cycling of the ovary and uterus
Ovarian cycle- stimulates development of ovarian follicles and production of oocyte
Uterine cycle- prepares the uterine wall for implantation and nourishment of a fertilized ovum
Characteristics of oogenesis
Formation and development of oocytes
Starts in ovary, finishes in uterine tube
1 primary oocyte yields 1 ovum and 2-3 polar bodies
Takes many years to complete
Process begins before birth and stalls until puberty
In fetus, oogonium replicates and gives rise to primary oocytes, which stall in meiosis 1 until puberty
After puberty ovarian cycle occurs with menstrual cycle and primary oocyte continues to differentiate
Phases of the ovarian cycle
Follicular phase (day 1-13)
Ovulation (on day 14)
Literal phase (day 15-28)
Characteristics of follicular phase of ovarian cycle
Follicle-stimulating hormone (FSH) stimulate 6-12 primordial follicles (primary oocyte + flat follicle cells)
Primordial follicle goes to become primary follicle (primary oocyte + cuboidal follicle cells)
Follicular cells multiply to form multiple layers now called granulosa cells in secondary follicle
Primary oocyte develops glycoprotein coat called zone pellucida
Fluid filled space forms in granulosa cells called antrum
Granulosa cells release estrogen into blood, stimulating changes in uterine lining
Primary oocyte completes meiosis 1 to form secondary oocyte, which is arrested in meiosis 2
Large quantity of luteinizing hormone causes volume of fluid to build in antrum, increasing size and pressure
Characteristics of ovulation
Mature follicle ruptures and releases secondary oocyte from one of two ovaries
Secondary oocyte is arrested in meiosis 2
Oocyte is swept into uterine tube by fimbriae
Secondary oocyte doesn’t complete meiosis 2 unless fertilized by sperm
Characteristics of luteal phase
After ovulation, remaining part of follicle collapses, called corpus luteum
Corpus luteum persists as an endocrine gland and secretes estrogen and progesterone
These hormones stimulate build up of endometrium in prep for pregnancy
If no implantation, corpus luteum dies after 2 weeeks and becomes scar like tissue called corpus albicans
Characteristics of Phases of menstrual cycle
Uterine phases are closely coordinated with ovarian cycle phases
At puberty, hypothalamus releases gonadotropin-releasing hormone which stimulates pituitary gland to release FSH and LG to initiate ovarian cycle
FSH and LH initiate changes in ovaries during oogenesis
Phases of uterine cycle
Menstrual phase -functional layer is shed on days 1-5
Proliferative phase- functional layer rebuilds from days 6-14
Secretory phase- endometrium prepares for Implantation days 15-28
Hormone characteristics of menstrual cycle
FSH stimulates growth of primordial follicles
Granulosa cells in secondary follicles release estrogen to rebuild functional layer of endometrium
LH increases fluid and pressure in tertiary oocyte until rupture (ovulation)
Corpus luteum releases estrogen and progesterone to prep endometrium for implantation
Characteristics of fertilization
Sperm cells deposited at the cervix travel through uterus to uterine tube
Oocyte can remain in reproductive tract for 24 hrs, sperm for 4 days
Fertilization is where one sperm cell fuses with oocyte to form new diploid cell in uterine tube
When sperm cell enters oocyte, oocyte completes meiosis 2
Characteristics of implantation
Fertilized ovum (zygote) moves to uterine cavity and divides
After 6 days, zygote implants in uterine wall (pregnancy)
Corpus luteum keeps producing progesterone to stabilize uterine lining (placenta at 3 months)
If no implantation, menstruation occurs and corpus luteum regresses, stopping production of progesterone and estrogen
What is an ectopic pregnancy
Occurs when a fertilized egg implants somewhere other than main cavity of uterus
Most often in uterine tubes, but can occur in abdomen or on surface of ovary
Fertilized egg can’t survive and can be fatal to mother if not treated
Characteristics of mammary glands
Modified sweat glands that only function in lactating individuals
Milk produced in lobes, travels through lactiferous ducts and accumulates in lactiferous sinus during nursing
Glandular tissue only develop halfway through pregnancy
Responds to hormonal stimulation
Components of mammary glands
Nipple- central protruding area
Areola- pigmented skin around nipple
Consists of 15-20 lobes
Lobes separated by connective tissue (suspensory ligaments)
Hormones stimulating the mammary glands
Prolactin- stimulates production of milk
Released by anterior pituitary gland
Oxytocin- stimulates ejection of milk
Released by posterior pituitary gland
