Female Reproductive System Study Guide Flashcards
Suspensory ligament
anchors each ovary laterally to the pelvic wall
Ovarian ligaments
anchors each ovary medially to the uterus
Mesovarium
suspends the ovary
Broad ligament
supports uterine tubes, uterus, and vagina. Suspensory ligament and mesovarium are portions of it
ovarian follicle
Tiny sac like structures embedded in the cortex
what an ovarian follicle contains
immature ova (oocytes) surrounded by
- Follicle cells (if only 1 cell layer is present)
- Granulosa cells (if more than 1 cell layer present)
Primordial follicle
single layer of follicle cells plus oocyte
More mature follicle
several layers of granulosa cells plus oocyte
Vesicular (antral or tertiary) follicle
a fully mature follicle in which a fluid-filled antrum has formed. The follicle bulges from the ovary surface
What happens in ovulation?
Ejection of the oocyte
corpus luteum
- Develops from the ruptured follicle after ovulation
- Formed by the remaining granulosa cells and internal thecal cells - secretes progesterone and some estrogen
corpus luteum upon degeneration
If no pregnancy occurs, it degenerates into corpus albicans in about 10 days
- (If pregnancy occurs, the corpus luteum produces hormones to sustain it until the placenta takes over at about 3 months)
fallopian/uterine tubes
receive ovulated oocyte, are the typical site of fertilization
Regions of fallopian/uterine tubes
isthmus, ampulla, infundibulum
isthmus
constricted area where tube joins uterus
Ampulla
distal end of the tube that curves around the ovary
Infundibulum
distal expansion near the ovary - contains fimbriae to create a current. Current sweeps ovulated oocyte into the tube. closure of the fimbriae makes the fallopian tube blocked, preventing the egg from moving on (and potentially being fertilized)
ectopic pregnancy
An oocyte is fertilized in the peritoneal cavity or in the distal uterine tube. It begins developing
- Typically results in a natural abortion with substantial bleeding
cervical glands
Secrete thick mucus to block sperm from entering the cervix outside the mid cycle time window
link between HPV and cervical cancer
Frequent UTIs, including HPV (sti) can cause cervical cancer
How is HPV detected?
pap smears
Mesometrium
lateral support for the uterus by the broad ligament
Cardinal (lateral cervical) ligaments
extend from the cervix and superior vagina to the lateral pelvic walls
Uterosacral ligaments
secure uterus to the sacrum
Round ligament
binds the uterus to the anterior wall
uterus position
tilts anteriorly away from the vaginal opening, anteversion (as opposed to retroversion - posterior tilt)
uterine prolapse
Despite ligaments, the uterus is primarily supported by the pelvic floor
- An unsupported uterus - such as might happen after childbirth, can sink inferiorly
Endometrium inner layers
Stratum functionalis - functional layer
Stratum basalis - basal layer
Stratum functionalis
Changes in response to ovarian hormone cycles
Is shed during menstruation
Stratum basalis
- Forms a new stratum functionalis after menstruation
- Is not responsive to ovarian hormones
What is the significance of the stratified squamous epithelium of the vagina. Why are acidic secretions important?
protection and stretch
analogous structures between the male and female external genitalia
- Labia majora and scrotum
- Great vestibular glands and bulbourethral glands
- Clitoris and penis (also has glans - exposed portion, and prepuce - hood that covers the glans)
perineum
Diamond shapes region between the pubic symphysis, coccyx, and the bilateral ischial tuberosities
milk producing structures
Glandular alveoli
structures that carry milk to the nipple
Milk is passed into lactiferous ducts and then into lactiferous sinuses. Sinuses open to the external body surface at the nipple
3 things that can increase a women’s risk of breast cancer
- Risk is proportional to lifetime exposure of estrogens - early puberty, late menopause, no or delayed pregnancies, and use of hormone replacement therapies can increase risk
- Risk is also increased by family history or genetic mutations in 1 of 2 genes - BRCA 1 or BRCA 2
screening exam for breast cancer
Mammogram
oogenesis
production of female gametes (like spermatogenesis)
When does oogenesis begin?
fetal period
At birth, a female infant has a lifetime supply of ____________
primary oocytes
dominant follicle
One primary oocyte is selected from the few primary oocytes that are activated each month to become the dominant follicle. It resumes meiosis I and creates two haploid cells - 1 secondary oocyte (large cell with almost all the parent cell’s cytoplasm and organelles), 1st polar body
cellular process during ovulation
Meiosis I - produces first polar body and secondary oocyte
polar body
very small cell, almost devoid of cytoplasm
What happens if a secondary oocyte is fertilized
it completes meiosis II creating 1 ovum (functional gamete) and 2nd polar body
What happens if a secondary oocyte is not fertilized
it deteriorates
net products of oogenesis
1 viable ovum + 2/3 polar bodies
net products of spermatogenesis
4 viable sperm
Similarities for spermatogenesis and oogenesis
- Diploid stem cells divide by mitosis
- Primary oo/spermatocytes undergo meiosis I
- Secondary oo/spermatocytes undergo meiosis II
- Ovum / sperm
typical ovarian cycle length
28 days
two phases of ovarian cycle
Follicular phase
Luteal phase
Follicular phase
day 1-14, period of vesicular follicle growth
Luteal phase
days 14 - 28, period of corpus luteum activity
Ovulation relative to ovarian cycle
end of the follicular phase and the luteal phase (around day 14)
Follicle
function unit of the ovary
Primordial follicles
1st follicle to develop in a female fetus, become primary follicles through oocyte enlargement and a change in the shape of the surrounding cells - squamous to cuboidal
Primary follicles
become secondary follicles when follicular cells proliferate to form stratified epithelium around the oocyte
A secondary follicle
becomes a vesicular follicle when a clear fluid-filled cavity called the antrum forms
Vesicular follicle
bulges from the external ovary surface and is ready to be ovulated
hormone that stimulates development of follicles
FSH - follicle stimulating hormone
what causes selection of the dominant follicle?
A drop in FSH levels
What hormone stimulates the rupturing of the ovarian wall?
LH - luteinizing hormone
sequencing of hormones for triggering follicle development, ovulation, and development of the corpus luteum.
GnRh stimulates secretion of FSH and LH
These 2 stimulate follicles to grow, mature, and secrete sex hormones
- Fsh stimulates granulosa cells to release estrogen
- Lh prods thecal cells to produce androgens - converted to estrogens
Increasing levels of plasma estrogen (and inhibin) stop release of fsh and lh, only dominant follicle withstands dip is fsh
Estrogen levels rise and trigger positive feedback surge in lh
Surge in lh triggers ovulation
Estrogen levels decline after ovulation, lh transforms ruptured follicle into corpus luteum
Corpus luteum secretes progesterone and some estrogen almost immediately
Rising levels of estrogen and progesterone in plasma inhibit the release of additional lh and fsh - inhibition is enhanced by inhibin
If no fertilization occurs, corpus luteum degenerates and estrogen / progesterone levels fall
Fsh and lh are secreted again, and the cycle restarts
What hormone plays an additional role in inhibiting the reproductive cycles?
Inhibin
How are the uterine and ovarian cycles related?
- The menstrual and proliferative phase of the uterine cycle overlap with the follicular phase of the ovarian cycle.
- The secretory phase of the uterine cycle overlap with the luteal phase phase of the ovarian cycle
3 phases of the uterine cycle
- Menstrual phase days 1-5
- Proliferative phase days 6-14
- Secretory (postovulatory) phase days 15-28
Menstrual phase
- Ovarian hormones are at their lowest levels
- Gonadotropin rises
- Stratum functionalis detaches from the uterine wall and is shed- flow of menstrual blood and tissue for 3-5 days
- By day 5, growing ovarian follicles start to produce more estrogen
Proliferative phase
- Rising estrogen levels prompt generation of a new stratum functionalis - layer thickens, glands enlarge, spiral arteries increase in number
- Estrogen increases the synthesis of progesterone receptors within the endometrium
- Normally thick, sticky cervical mucus is thinned out to facilitate the passage of sperm
- Ovulation occurs around day 14
Secretory (postovulatory) phase
- Phase that is most consistent in duration
- Endometrium is prepared for possible implantation
- Rising progesterone levels from the corpus luteum prompt
– Endometrial glands to enlarge and secrete nutrients
– Formation of a cervical mucus plug to block entry of more sperm, pathogens, debris
amenorrhea
cessation of menstruation (typically reversible, but bone loss is not)
- Adipose cells help convert adrenal androgens to estrogens and are a source of leptin
Leptin
hormone that plays a critical, permissive role in the onset of puberty
danger of amenorrhea
Once estrogen levels drop and the menstrual cycle stops, bone loss begins, leading to osteoporosis
role between estrogen and bone health
Supports rapid short lived growth spurts
Widening and lightening of pelvis
Sustains bone density
estrogen and cardiac health
Maintains low total blood cholesterol and high hdl levels
Facilitates calcium uptake
systemic effects of estrogen
- Promote oogenesis and follicle growth in the ovaries
- Exert anabolic effects on the female reproductive tract
- Induce secondary sex characteristics - growth of breasts and deposits of fat in the hips
role of progesterone in maintaining pregnancy
- Works with estrogen to establish and regulate uterine cycle
- Promotes changes in cervical mucus
- Inhibits uterine motility during pregnancy
- Prepares breasts for lactation
How genetic sex is determined
Xx = female xy = male
Which parent determines genetic sex of offspring
Men determine the sex because they have two different chromosomes they can pass down, females only have one
SRY gene
Single gene on the y chromosome that determines maleness by initiating development of testes
nondisjunction
Abnormal distribution of any chromosome to the gametes
Trisomy 21
down’s syndrome, one extra chromosome 21
Turners syndrome
females with only 1 x chromosome (XO) that never develop ovaries; at risk for shorter stature, learning challenges, and heart defects
Klinefelter’s syndrome
males with 2+ x chromosomes and 1 y chromosome - results in sterility, at risk for learning challenges
The presence or absence of which hormone determines sexual differentiation?
testosterone
