chapter 28: female reproductive system

female gonads that produce egg cells (ova) and sex hormones

ovaries

what develops in the outer cortex layer of the tunica albuginea of the ovaries

germ cells

what is in the medulla layer of the tunica albuginea of the ovaries

major arteries & veins

release of the ova into the fallopian tubes

ovulation

canals about 10 cm long leading from ovary to uterus. wall is muscular (smooth), lined with ciliated cells and secretory cells that help move the egg towards the uterus. normal cite of fertilization

uterine tubes (oviduct/fallopian tubes)

thick muscular chamber that opens into roof of vagina. harbors fetus, provides a source of nutrition, and expels the fetus at the end of its development

uterus (womb)

what is the purpose of the cervix and mucus in the uterus?

sperm reservoir, & protect sperm from acidic environment of vagina and from phagocytes/WBCs

#1 cause of cervical cancer

HPV

how does a pap smear work

loose cells from the cervix/vagina are removed and microscopically examined to test for cervical cancer

class 1 of cervical intraepithelial neoplasia (cervical cancer)

mild dysplasia

class 2 of cervical intraepithelial neoplasia (cervical cancer)

calls for biopsy

class 3 of cervical intraepithelial neoplasia (cervical cancer)

may call for radiation therapy or a hysterectomy

3 layers of the uterine wall:

perimetrium, myometrium,& endometrium

outermost layer of uterus. thin serosa of simple squamous epithelium and loose connective tissue

perimetrium

middle muscular layer of uterus. composed mainly of smooth muscle & produces labor contractions, & expels fetus and menstrual fluids

myometrium

inner glandular mucosa of uterus. simple columnar epithelium, compound tubular glands, and a stroma populated with leukocytes, macrophages, and other cells. develops tissue and ceratory glands in preparation for implantation of a developing embryo. comprised of 2 layers: functional and basal

endometrium

superficial half of endometrium (2/3), shed in each menstrual period

functional layer

deep layer of endometrium, stays behind and regenerates a new functional layer with each menstrual cycle

basal layer

growth of endometrial tissue outside of the uterus (uterine tubes, surface of ovaries, urinary bladder, vagina, pelvic cavity, peritoneum, intestines, or even lungs and pleural cavity) causing pain and sometimes infertility

endometriosis

what is believed to be the cause of endometriosis?

retrograde menstruation, a backwards flow of menstrual fluid that exits uterine tubes

sequence of events from fertilization to giving birth and returning to fertility

reproductive cycle

recurs every month that no pregnancy occurs. rhythmic changes in ovaries and uterus that correlate with oogenesis and folliculogenesis. comprised of 2 parts: ovarian (events in ovaries) & menstrual (parallel changes in uterus) cycles

sexual cycle

egg production

oogenesis

when do female germ cells colonize gonadal ridges in utero causing them to differentiate into oogonia and multiply into the 5th month of pregnancy?

first 5 to 6 weeks of development

average number of oogonia one has shortly before birth

6 to 7 million

what do oogonia transform into before birth?

primary oocytes

any stage from the primary oocyte to the time of fertilization is considered a

egg/ovum

how many oocytes remain by puberty?

200,000

what stimulates oocytes to continue meiosis I when puberty starts?

follicle stimulating hormone (FSH)

on the day of ovulation, meiosis I is completed & what happens?

2 daughter cells are produced: a large (secondary oocyte) & small (first polar body) one

why does the first polar body & its daughter cells degenerate?

to discard extra chromosomes & leave cellular material to the secondary oocyte

why does the secondary oocyte have as much of a cytoplasm as possible?

if fertilized, it needs enough material to divide repeatedly & produce numerous cells

how far does the secondary oocyte get in meiosis II? (remember if it is not fertilized, it will die and never finish)

metaphase II

what happens if a secondary oocyte is fertilized?

it completes meiosis II and sheds off a second polar body

what is the average length of the sexual cycle?

28 days

Basic hierarchy of hormonal control (each influences the other in order until it reaches the ovaries which influence the uterus):

hypothalamo-pituitary-ovarian axis

oogenesis is apart of which cycle in the sexual cycle?

ovarian cycle

ova are produced by follicles in the ovaries and their development is inlufced by FSH, but what triggers the monthly release of the ovum?

luteinizing hormone

2 phases of the ovarian cycle

follicular & luteal phase

how many days is the follicular cycle?

14, beginning on day 1 of menstration

days 1-5 of the follicular phase of the ovarian cycle

FSH is released by the pituitary causing primary follicles & ovum to mature into secondary follicles & secondary oocytes

days 6-14 of the follicular phase of the ovarian cycle

follicle releases estrogen, influenced by luteinizing hormone. uterus replaces lost tissue by mitosis

day 14 of the follicular phase of the ovarian cycle

luteinizing hormone peaks and ovulation occurs

days 14-28 of the luteal phase of the ovarian cycle

ovulation occurs (due to LH), the ruptured follicle stays in the ovary, becoming corpus luteum to secrete estradiol & progesterone to thicken the endometrium (breaks down if no pregnancy occurs) and eventually becoming corpus albicans (scar tissue) if no pregnancy occurs

The development and maintenance of the endometrium is controlled primarily by ____ & ____

estrogen & progesterone

when do females stop making estrogen?

when no more corpus luteum is developed due to the body running out of oocytes (stops ovulation)

Rupture of endometrial capillaries and shedding of the endometrium occur

menses phase of the menstrual cycle (day 1-7)

Rapid growth of endometrium

proliferative phase of the menstrual cycle (days 8-13)

begins at ovulation, endometrial glands enlarge and increase secretion. arteries grow into endometrium

secretory phase of the menstrual cycle (days 14-28)

what happens around day 22 of the luteal phase (sexual cycle) if no pregnancy occurs?

involution (shrinkage)

what happens around day 26 of the luteal phase (sexual cycle) if no pregnancy occurs?

involution is complete & only scar tissue (corpus albicans) remains. estrogen & progesterone secretion drops bc corpus luteum degenerates. FSH levels rise and stimulate new follicles

If pregnancy does not occur, what occurs in the luteal (postovulatory) phase (days 15-28)

corpus luteum becomes corpus albicans, estrogen and progesterone secretion decrease & the endometrium starts to shed

If pregnancy occurs, what occurs in the luteal (postovulatory) phase (days 15-28)

Corpus luteum is maintained & LH stimulates it to grow and secrete estrogen and progesterone. these estrogen and progesterone levels are maintained until the placenta takes over