Lecture 11: Female reproductive system Flashcards
What is the function of the female reproductive system
- to produce offspring and ensure continuity of the genetic code
- to produce eggs, or female gametes, each can unite with male gamete to form the first cell of an offspring
- to provide nutrition and protection to the offspring for up to several years after conception
What are the 4 parts that make up the female reproductive system
- Gonads
- Hormones
- Organ systems
- Reproductive cycles
What are the Gonads
- ovaries (oogenesis occurs here)
- gamete: 2nd oocyte (can lead to ovule)
What are the hormones of female reproductive sys.
- Estrogen & Progestrone
- Inhibin & Relaxin
What are the 3 parts of the organ system
- Internal genitalia (ovaries & duct system)
- External genitalia (Vulva)
- Accessory organs (mammary glands)
What are the 3 independent reproductive cycles of female repro sys
- Ovarian cycle (oogenesis & developmentt of folicles)
- Menstrual cycles (shedding of the endometrium of the uterus)
- Hormonal cycle (control of the other 2 cycles & mammary gland -> secretion and production)
what is structure and location of ovaries
- site of female gamete production
- homologus to the testes of the male
- held in peritoneal cavity by many ligaments
What are the 3 ligaments holding ovaries in place
- Broad ligament (attaches the ovaries to the uterus)
- Ovarian ligament (holds ovary to uterus)
- Suspensory ligament (attaches the ovaries to the pelvic wall)
How does irrigation work in the ovaries
- abdominal aorta sends to the ovarian artery
- internal iliac artery sends to a branch of the uterine artery
- ovarian veins form the PAMPINIFORM plexus
Structure of germinal epithelium in ovaries
- external covering
- continuous w/ peritoneum
- cuboidal or squamous epithelium
- covering ovaries
What is structure of tunica Albuginea of ovaries
- internal capsule
- made of c.t.
what is structure of cortex of the ovaries
- dense layer
- highly vascularized
- containing ovarian follicles
What do the ovarian follicles contin
- Oocytes (immature future ovules at diff stages of devel) & a few layers of epithelial tissue that surrounds them
- all devel in first 6 months of fetus life
- have ~ 400, 000 total but only 400 survive
- 400/ 12 mnths = 33 years after puberty to have a baby
What is structure of medulla of ovaries
loose tissue housing blood vessels & nerves
What does oogenesis genrate
the female gamete
What is the progress of oogenesis
primary oocyte -> secondary oocyte -> ovum
How many Oocytes develop at a time and how does this differ from spermatogonium
-1 oocyte will develop at a time
vs
-4 spermatozoa
What happens to first and second polar bodies
they are broken down and then reabsorbed
What is first form of follicular phase
-primordial follicle
then becomes primary follicle
When does primordial follicle become primary follicle
when the 1 layer of follicular cells surround oocyte
What happens when follicular cells of primary follicle proliferate
- they become stratified
- take on a new name : Granulosa cell
What is the name of the connective tissue (c.t.) that forms around the primary follicle
Theca cells (internal & external)
What do the internal theca cells secrete
androgens
What do Granulosa cells do to androgens secreted by the internal theca cells
converts them to estrogen
What does the external theca cells transform into
fibrous capsule
What forms the thick transparent membrane around the primary oocyte aka ZONA PELLUCIDA
granule cells secrete a rich substance in glycoproteins (receptors for spermatozoa)
When the ZONA PELLUCIDA is secreted around the primary oocyte what stage of follicular phase is that
secondary follicle
What is the ANTRUM
a cavity between granule cells filled with follicular liquid
What do you call the granulosa cells that surround the zona pellucida that is secreted by the oocyte
corona radiata
What is name for follicle at maximum size
Vesicular (Graafian) follicle
10-12mm
What is size of ovum
~120um
-which = ~ 250,000 times the size of sperm
Why does Graafian follicle bulge from surface of the ovary
so that it will rrupture
What is released into the peritoneal cavity after the Graafian follicle ruptures from the ovary and what is this process called
- secondary oocyte and corona radiata are released
- this is called ovulation
What is the process called Atresia
-many follicles are at different stages of maturation but only 1 becomes the dominant follicle and continues on to ovulation while the others degenrate
What comes after follicular phase
Luteal phase
What happens to Graafian follicle after the evacuation of follicular liquid (luteal phase)
- Graafian follicle flattens
- antrum if filled with coagulated blood
- blood is absorbed by granulosa cells (corpus hemorrhagicum)
What happens after granulosa cells absorb blood in luteal phase
Granulosa cells hypertrophy
- fuses w/ the internal theca cells
- forms the corpus luteum
- “yellow body”
What is the transient endocrine gland formed in the luteal phase
corpus luteum
What does the Corpus Luteum secrete
- Progesteron
- a bit of Estrogen
- Inhibin (suppress FSH and development of more follicles)
What happens to Corpus Luteum if there is NO pregnancy
- begins to degenerate after 10 days
- stops producing hormones
What happens to Corpus Luteum if there IS pregnancy
-it will be active until placenta is ready to secrete hormones in its place
~ the end of 3 months where corpus luteum will degenerate & ovaries will remain inactive until delivery (parturition)
What hormone regulates ovarian cycle
fluctuation of gonadotropin levels
Ovarian cycle is correlated with what other cycle
uterine cycle
Fluctuations of what hormone levels will cause endometrial changes
fluctuations of ovarian hormone levels
What are the hormones involved with ovarian cycle
FSH: follicle stimulating hormone
LH: luteinizing hormone
-both peak at ovulation day 14
Uterine cycle is a series of what and occurs in response to what hormones
- series of cyclic modifications that occur to the uterus’ endometrium
- occurs each month in response to estrogen and progestrone
Uterine cycle occurs in how many phases
3