A&P 3 - Ch 28 Female Reproduction

The first menstrual period is called...

Menarche

How does body fat relate to menstruation?

Menstruation requires a minimum level of body fat to support pregnancy. If body fat falls below 17% in teenagers, menarche does not occur. If body fat falls below 22% in adults, menstruation ceases.

More on the mesovarium?

Mesovarium extends to a sheet of peritoneum called the broad ligament, which flanks the uterus and encloses the uterine tube in its superior margin

What are the two sections of the uterine tube that lead from the infundibulum to the uterus?

Middle section is ampulla; inner section is isthmus

Without defining the anatomy of the external genitalia, what should we be familiar with?

Mons pubis, labia majora and minora, prepuce, clitoris, vestibule, vaginal and urethral orifices, perineal raphe

Is breast cancer typically hereditary or nonhereditary?

Most breast cancer is nonherditary

After ovulation, we enter the luteal (postovulatory) phase. What happens to the ruptured follicle?

Ovulated follicle collapses and transforms into the corpus luteum

What procedure is used to check for cervical cancer?

Pap smear, removal and examination of cells from cervix and vagina

What are the three layers of the uterine wall?

Perimetrium: external serosa Myometrium: middle muscular layer Endometrium: inner mucosa

Which glands change during pregnancy?

Pituitary and thyroid glands become about 50% larger, producing more hormones and increasing metabolic rate. Parathyroid glands enlarge and increase osteoclast activity.

In addition to events in the ovaries and uterus, what third anatomy plays a major role in the sexual cycle?

Pituitary gland, which secretes FSH and LH and drives the whole thing

What is the action of progesterone?

Prevents menstruation and thickens endometrium

What is the action of progesterone?

Primarily acts on the uterus preparing it for possible pregnancy in the second half of the menstrual cycle

What anatomy produces these hormones?

Primarily the placenta, but also the corpus luteum. Corpus luteum produces for the first 7 weeks, and placenta takes over for weeks 7 to 17.

What type of tissue is the endometrium?

Simple columnar epithelium

What kind of tissue lines forms the vaginal epithelium?

Simple cuboidal in childhood, transforming in puberty d/t the action of estrogens into stratified squamous epithelium

What is the action of GnRH?

Stimulates the anterior lobe of the pituitary to produce follicle-stiumlating hormone (FSH) and luteinizing hormone (LH)

What is the action of Human chorionic gonadotropin (HCG)?

Stimulates the growth of the corpus luteum, which secretes increasing amounts of progesterone and estrogen

Describe the anatomy of a mammary gland that has developed during pregnancy

15 to 20 lobes arranged radially around the nipple. Each lobe is drained by a lactiferous duct, which dilates to form a lactiferous sinus opening onto the nipple.

What hormones dominate the ovarian and menstrual cycles at what times?

- FSH dominates the ovarian cycle from days 0 to 13 - LSH dominates the ovarian cycle from days 14 to 28 - Estrogen dominates the menstrual cycle from days 0 to 14 - Progesterone dominates the menstrual cycle from days 14 to 28

What are the two phases of the sexual cycle?

- Follicular phase - first 2 weeks of cycle, beginning with 3-5 days of menstruation, ending with ovulation on day 14 - Luteal phase - corpus luteum stimulates endometrial secretion and thickening

What four ligaments support the uterus and hold it in place?

- Mesometrium: portion of broad ligament on each side of uterus - Cardinal (lateral cervical) ligaments: extending to pelvic wall - Uterosacral ligaments: attach posterior side of uterus to sacrum - Round ligaments: arise from anterior side of uterus, pass through inguinal canals, terminate in labia majora

What arteries supply the ovaries, uterus and vagina? From where do these arise?

- Ovarian artery arises from the aorta, passes through the suspensory ligament and supplies the ovaries - Uterine and vaginal arteries arise from the internal iliac arteries and supply their namesakes

What adjustments to pregnancy did Dr. Cone talk about?

- pressure on the urine bladder - morning sickness - reduced GI motility, which can cause constipation and heartburn

List some of the risk factors for breast cancer

-Aging, exposure to ionizing radiation, carcinogenic chemicals, excessive alcohol and fat intake, and smoking -70% of cases lack identifiable risk factors

What four hormones have the strongest influence on pregnancy?

-Estrogens -Progesterone -Human chorionic gonadotropin -Human chorionic somatomammotropin

Lots of changes happen during climacteric. What are these? * definitely touched on in class, but too many to memorize, not emphasized to a great degree

-Follicles less responsive to gonadotropins -Less estrogen and progesterone secretion -Uterus, vagina, and breast atrophy -Intercourse becomes uncomfortable as vagina becomes thinner, less distensible, and drier -Vaginal infections more common -Skin becomes thinner -Cholesterol levels rise increasing the risk of cardiovascular disease -Bone mass declines producing increased risk for osteoporosis -Blood vessels constrict and dilate in response to shifting hormone balances -Hot flashes: spreading sense of heat from the abdomen to the thorax, neck, and face

What are the four functions of the female reproductive system?

-Produces and delivers gametes -Provides nutrition and safe harbor for fetal development -Gives birth -Nourishes infant

What are the five effects of estradiol at puberty?

-Stimulates vaginal metaplasia -Stimulates growth of ovaries and secondary sex organs -Stimulates growth hormone secretion (increase in height and widening of the pelvis) -Responsible for feminine physique because it stimulates the deposition of fat -Makes a girl's skin thicker

Why is the secretion of estradiol by the maturing follicle so important?

1) A surge in estradiol stimulates the hypothalamus and anterior pituitary. 2) In response, the anterior pituitary secretes a spike in LH and smaller increase in FSH. 3) Increased LH triggers ovulation. 4) Ovulation leads to the corpus luteum secreting progesterone, which acts on the uterus. 5) Absence of HCG causes menstruation.

What are the three principal steps of the ovarian cycle?

1) Follicular phase 2) Ovulation 3) Luteal phase

What are the four phases of the menstrual cycle? * not covered in class, but helpful for comprehension IMO

1) proliferative phase 2) secretory phase 3) premenstrual phase 4) menstrual phase

How many oocytes are girls born with? How many remain when girls begin puberty? What is this process of degeneration of oocytes called?

2 mil at birth, 400,000 upon puberty Degeneration of oocytes is called atresia

What is the average length of the sexual cycle?

28 days, varying from 20 to 45 days

What is the most important hormonal event to understand regarding the sexual cycle?

A maturing follicle secretes estradiol. This single event sets off a chain reaction from ovulation through to the end of the sexual cycle.

What three additional hormones have increasing secretion during pregnancy?

ACTH, Aldosterone, Relaxin

What hormone actions trigger the development of the female reproductive tract?

Absence (not presence) of testosterone and müllerian-inhibiting factor (MIF)

The absence of the testosterone and MIF are responsible for the development of the inner and outer genitalia. Which is which?

Absence of testosterone leads to development of outer genitalia. Absence of MIF leads to development of inner genitalia.

What is the action of Human chorionic somatomammotropin (HCS)?

Action similar to growth hormone but weaker. Reduces mother's insulin sensitivity and glucose usage, leaving more for the fetus (big appetite).

When do sex characteristics become apparent in the human embryo?

After 6 to 8 weeks; prior to this the two sexes are indistinguishable

What is the midportion of the uterus?

Body or corpus

What is the action of estrogens?

Causes tissue growth in the fetus and mother. Uterus and external genitalia enlarge, mammary ducts grow, breast size increases, pubic symphysis relaxes, pelvis widens.

Why are pap smears important?

Cervical cancer is common in women between ages 30 and 50. If discovered early, removal is easy. If cancerous cells spread to subepithelial connective tissue, the cancer is invasive and much more dangerous. Risk factors include smoking, early-age sexual activity, STDs and human papillomavirus.

What is the inferior end of the uterus?

Cervix

At what age does climacteric typically occur?

Climacteric does not begin at a specific age but rather when a female has abou 1,000 follicles left

What is the midlife change in women's hormone secretion called? What event accompanies this?

Climacteric, accompanied by menopause, the cessation of menstruation

What mechanisms protect the vagina from infection?

Epithelial cells are rich in glycogen, which bacteria ferment to lactic acid, producing a protectively low pH. Also contain high concentration of dendritic cells.

What happens during ovulation? When does it occur?

Estradiol stimulates a surge of LH and lesser spike by FSH. Among other events, follicular fluid builds up rapidly in the follicle, the follicular walls is weakened by inflammation and enzymes, and the follicle ruptures, releasing its egg and attendant cells. Ovulation typically occurs around day 14.

What hormones does the ovary generate during the first and second half of its cycle?

Estrogen during the first half Progesterone during the second half

What is the action of estrogens? What are the three varieties of estrogens?

Estrogens are feminizing hormones with widespread effects on the body Estrogens include: Estradiol (most abundant), estriol, and estrone

What is the action of FSH?

FSH stimulates developing ovarian follicles and they begin to secrete estrogen, progesterone, inhibin, and a small amount of androgen

What happens during the follicular phase?

FSH stimulates growth of a cohort of follicles. During a 5 day window, one is selected as the dominant follicle, which becomes more sensitive and grows more than the others while the others degenerate. The end of the follicular phase is marked by ovulation.

What is one of the differences between male and female reproductive systems in terms of hormone production?

Female system is more cyclic whereas male is a relatively steady secretion

Where can I see this process illustrated?

Figure 28.13 illustrates control of ovulation, and 28.14 graphs the hormone release that occurs during both the ovarian and menstrual cycles.

What are the feathery projections off the infundibulum?

Fimbriae

What is the valley separating the base of the cervix from the vaginal wall?

Fornix

What is the broad superior curvature of the uterus called?

Fundus

What hormone keeps the corpus luteum from involuting?

Human chorionic gonadotropin (HCG), produced by the zygote. This feeds back to the corpus luteum and keeps it churning out progesterone until the third trimester of pregnancy.

What is the basic hierarchy of hormonal control?

Hypothalamus -> pituitary -> ovaries -> uterus

How long does the corpus luteum secrete estradiol and progesterone?

If pregnancy occurs, the corpus luteum will continue its secretion until the third trimester. If pregnancy does not occur, it begins the process of involution around day 22 (8 days after ovulation) and becomes inactive scar tissue called the corpus albicans by day 26.

What is the function of the corpus luteum?

In response to LH, the corpus luteum continues to grow and secretes rising levels of estradiol and progesterone. Progesterone prepares the uterus for the possibility of pregnancy.

What is the flared, trumpetlike anatomy at the lateral end of the uterine tube?

Infundibulum

What anatomy makes up the female internal and external genitalia?

Internal: ovaries, uterine tubes, uterus and vagina External: clitoris, labia minora and labia majora

Does ovulation occur with menarche?

No, the first few menstrual cycles are anovulatory, and ovulation typically begins about a year after menstruation

Do eggs emerge from the ovaries through ducts?

No, they rupture through the surface of the ovaries in fluid-filled bubblelike follicles

What happens during the premenstrual phase?

Occuring during the last 2 days of the cycle, the endometrium degenerates in response to a sharp decline in progesterone being secreted by the corpus luteum. Spasmodic contractions of the spiral arteries of the endometrium causes ischemia and tissue necrosis. The necrotic stratum functionalis falls away from the uterine wall.

What happens during the menstrual phase?

Occurring during the first 5 days of the sexual cycle, menstrual fluid is discharged from the vagina. On average, 40 mL of blood and 35 mL of serous fluid is expelled over a 5-day period.

What happens during the secretory phase?

Occurring from days 15 through 26, the endometrium thickens still more in response to progesterone from the corpus luteum. The endometrium is primed for embryonic development.

Describe the three ligaments that are responsible for holding the ovaries in place.

Ovaries held in place medially by the ovarian ligament, laterally by the suspensory ligament, anterior margin held in place by peritoneal fold called mesovarium

What anatomy makes up the female primary and secondary sex organs?

Primary: ovaries Secondary: other internal and external genitalia

What hormone triggers development of the mammary glands during pregnancy?

Prolactin

The appearance of pubic hair, axillary hair, sebaceous glands and axillary glands is called...

Pubarche

At what age does puberty begin for most girls? What triggers puberty?

Puberty begins at age 8 to 10, triggered by rising levels of GnRH

How can a couple attempting to conceive a child tell that ovulation occurs?

Resting body temperature rises 0.4 to 0.6 degrees, best measured first thing in the morning. * cervical mucus also becomes thinner and more stretchy, but it's probably not something you want to monitor

What are the two layers of the endometrium and their functions?

Stratum functionalis: superficial half to two-thirds shed in each menstrual period Stratum basalis: stays behind and regenerates new stratum functionalis in the next cycle

What are the superior and inferior openings of the cervical canal?

Superior opening of canal into body of uterus is internal os Inferior opening of canal into vagina is external os

Through which of these three ligaments do the ovarian artery and vein pass to supply blood to the ovary?

Suspensory ligament

The upper two corners of the uterus open to the uterine tubes. What anatomy connects the lumen of the uterus to the vagina?

The cervical canal

Summarize what happens during the menstrual cycle

The endometrium builds up through most of the sexual cycle, followed by its breakdown and vaginal discharge.

What happens during the proliferative phase?

The layer of endometrial tissue (stratum functionalis) lost in the last menstruation is rebuild. This occurs from about day 6 to day 14 or 15 when ovulation occurs. Days 1 through 5 are the menstrual phase.

The uterine tube is enfolded in the superior margin of the broad margin known as...

The mesosalpinx

From what anatomy does the female reproductive tract develop?

The paramesonephric ducts

Where does the egg go following ovulation?

The uterine tube catches the oocyte, and cilia create a gentle current in the peritoneal fluid that pulls the oocyte into the uterus.

The onset of breast development is the earliest sign of puberty and is called...

Thelarche

What effect do estrogens and progesterone have on FSH and LH secretion?

These suppress FSH and LH secretion through negative feedback; elevated levels of estrogen suppress FSH secretion, while elevated levels of progesterone suppress LH secretion

What happens to the areola and nipple during pregnancy?

They darken, making them more visible to a nursing infant

What is the outer capsule of the ovaries?

Tunica albuginea

What two factors have been identified that promote the development of breast cancer?

Two breast genes: BRCA1 and BRCA2 Some forms of breast cancer stimulated by long periods of fertility and estrogen exposure

What anatomy is responsible for communication of eggs from the ovaries to the uterus?

Uterine tube, aka oviduct or fallopian tube

How is the vagina lubricated?

Vagina has no glands but lubricates by transudation ("vaginal sweating") of serous fluid through its walls and by mucus from the cervical glands above it

What area of the ovaries consists of major arteries and veins? What area is where germ cells develop?

Venous area is the inner medulla. Germ cell development occurs in the outer cortex.

What subcutaneous erectile tissue bracket the vagina and become congested with blood during sexual excitement, aiding stimulation?

Vestibular bulbs

The external genitalia are collectively called...

Vulva or pudendum * pudend = shameful (obviously)

Is that it for the ovarian cycle?

Yep, just focus on the hormones and their actions, follicles, ovulation and the corpus luteum, and you should be golden!

What is the german term for twinges of ovarian pain?

mittelschmerz * not tested, but thought this was funny

The sexual cycle consists of two interrelated cycles controlled by shifting patterns of hormone secretion. What are these two cycles?

•Ovarian cycle—events in ovaries •Menstrual cycle—parallel changes in uterus