Exam 4 pt. 4

Question 1

Review the ligaments supporting the uterus and the ligaments supporting the ovaries.

Answer 1

o Paired, almond-sized structures
o Held in place by several ligaments
 Ovarian Ligaments: anchors each ovary medially to the uterus
 Suspensory Ligament: anchors each ovary laterally to the pelvic wall
 Mesovarium: suspends the ovary
o Suspensory ligament and mesovarium are portions of the broad ligament
o The broad ligament supports uterine tubes, uterus, and vagina

Question 2

• What is an ovarian follicle? Where would you find it in the ovary? What does it contain?

Answer 2

o Ovarian Follicles: tiny saclike structures embedded in the cortex
 Contain immature ova (oocytes) surrounded by:
* Follicle Cells (if only 1 cell layer is present)
* Granulosa Cells (if more than 1 cell layer is present)
 Follicles go through several stages of development
* 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.

Question 3

• What is a primordial follicle? A vesicular? What’s an antrum?

Question 4

• What happens in ovulation?

Answer 4

o Ovulation: ejection of the oocyte

Question 5

• Define corpus luteum. What is its functional role? What does the corpus luteum become upon degeneration?

Answer 5

o Corpus Luteum develops from the ruptured follicle after ovulation

Question 6

• Review the portions of the fallopian/uterine tubes. What are fimbriae? What is the medical importance of fimbriae? What does their existence mean about the open vs closed circuitry of the female reproductive tract?

Answer 6

o Fallopian/Uterine Tubes do NOT have direct contact with the ovaries
o An ovulated oocyte is cast into the peritoneal cavity – some oocytes will never enter the tube system
o Tube System:
 Fallopian/Uterine Tubes
 Uterus
 Vagina
o The fallopian/uterine tubes – also sometimes called the oviducts – receive an ovulated oocyte
o The fallopian/uterine tubes are the typical site of fertilization
o Each tube extends from the ovary to the superolateral region of the uterus
o Each tube is covered by peritoneum and supported by a short mesentery called the mesosalpinx
o Regions of the Fallopian/Uterine Tube:
 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 ciliated fimbriae to create a current. Current sweeps the ovulated oocyte into the tube.
o The oocyte is carried towards the uterus by smooth muscle peristalsis + ciliary action
o Non-ciliated cells of the tube function to nourish both the oocyte and the sperm

Question 7

Review the portions of the fallopian/uterine tubes

Answer 7

o Fallopian/Uterine Tubes do NOT have direct contact with the ovaries
o An ovulated oocyte is cast into the peritoneal cavity – some oocytes will never enter the tube system
o Tube System:
 Fallopian/Uterine Tubes
 Uterus
 Vagina

Question 8

What are fimbriae? What is the medical importance of fimbriae? What does their existence mean about the open vs closed circuitry of the female reproductive tract? `

Question 9

• What’s an ectopic pregnancy?

Answer 9

o 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

Question 10

• Be prepared to label the portions of the uterus in a picture.

Answer 10

o Hollow, thick-walled, muscular organ
o Function: receive, retain, and nourish a fertilized ovum
o Regions of the Uterus:
 Body: major portion
 Fundus: rounded, superior region
 Isthmus: narrowed, inferior region
 Cervix: narrowed neck/outlet, projects into vagina
 Cervical Canal: communicates with the vagina via external os, and the uterine body via the internal os
o Cervical Glands: secrete thick mucus to block sperm from entering the cervix outside of the midcycle time window

Question 11

• What role do cervical glands play?

Answer 11

o Cervical Glands: secrete thick mucus to block sperm from entering the cervix outside of the midcycle time window

Question 12

• Review the link between HPV and cervical cancer. How is HPV detected?

Answer 12

o Cervical Cancer
 Affects 450,000 women worldwide/year
 1/2 of cervical cancer cases are fatal
 Most common between the ages of 30 and 50
 Risk Factors: frequent cervical inflammation, history of STIs (including HPV), multiple pregnancies
 Gardasil: vaccine against HPV, administered in 3 doses; recommended at age ~11-12
 Detection by Papanicolaou (Pap) Smears - recommended for every 3 years for ages 21-30 and every 5 years for ages 30-65

Question 13

• What ligaments support the positioning of the uterus? How is the uterus typically positioned in the sagittal plane?

Answer 13

o Mesometrium: lateral support by the broad ligament
o Cardinal (Lateral Cervical) Ligaments: extend from the cervix and superior vagina to the lateral pelvic walls
o Uterosacral Ligaments: secure uterus to the sacrum
o Round Ligament: binds the uterus to the anterior wall

Question 14

• Define uterine prolapse.

Answer 14

o Uterine Prolapse: despite ligaments, the uterus is primarily supported by the pelvic floor
o An unsupported uterus – such as might happen after childbirth – can sink inferiorly

Question 15

Be prepared to label the 3 layers of the uterine wall. And define the two layers within the innermost layer. Which layer is sloughed off in menstrual flow?

Answer 15

o Perimetrium: outermost, serous layer (visceral peritoneum)
o Myometrium: bulky middle layer, consists of interlacing layers of smooth muscle
 Provides the powerful, rhythmic contractions needed for childbirth
o Endometrium: mucosal lining
 Simple columnar epithelium atop a thick lamina propria
 A fertilized egg burrows into the endometrium and resides there during development
 The endometrium has two chief layers called strata
* Stratum Functionalis: the functional layer
o Changes in response to ovarian hormone cycles
o Is shed during menstruation
* Stratum Basalis: the basal layer
o Forms a new stratum functionalis after menstruation
o Is not responsive to ovarian hormones

Question 16

• What is the significance of the stratified squamous epithelium of the vagina. Why are acidic secretions important?

Question 17

• Review what are the analogous structures between the male and female external genitalia. (For example, labia majora and scrotum.)

Answer 17

o Vulva/Pudendum: female external genitalia
 Mons Pubis: fatty area overlaying the pubic symphysis
 Labia Majora: fatty skin folds – counterpart to the male scrotum
 Labia Minora: skin folds within the labia majora
 Vestibule: recess within the labia minora
o Great Vestibular Glands
 Flank the vaginal opening
 Homologous to the bulbourethral glands
 Release mucus into the vestibule for lubrication
o Clitoris
 Anterior to the vestibule
 Homologous to the penis
 Glans of the Clitoris: exposed portion
 Prepuce of the Clitoris: hood that covers the glans

Question 18

• What area is defined as the perineum? What are the borders?

Answer 18

o Diamond shaped region between the pubic symphysis, coccyx, and the bilateral ischial tuberosities

Question 19

• Within the mammary gland, what are the milk producing structures? What structures carry milk to the nipple?

Answer 19

o Mammary Glands are present in both males and females, but they are only functional in females
o Mammary glands are modified sweat glands consisting of 15-25 lobes
o Function: production of milk to nourish a newborn
o Areola: pigmented skin around the nipple – functions in latching
o Suspensory Ligaments: connective tissue that attaches breast to underlying muscle and overlying dermis
o Lobules within each lobe contain glandular alveoli
o Glandular alveoli are the milk-producing structures
o Milk is passed into lactiferous ducts and then into lactiferous sinuses
o Sinuses open to the external body surface at the nipple
o In non-nursing women, glandular structures are undeveloped
o Differences in breast size are due to differences in the amount of fat deposits

Question 20

• List 3 things that can increase a women’s risk of breast cancer. What is the screening exam for breast cancer?

Answer 20

o Breast Cancer
 The 2nd most common cancer in American women
 1:8 American women develops breast cancer
 5-year survival rate is 90%
 Typically arises in the epithelial cells of the smallest ducts and becomes a lump from which cells may metastasize
 Risk is proportional to lifetime exposure to 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
o Mammogram
 Routine x-ray examination of breast tissue
 Recommended every year for women aged 45-54; every 2 years for women aged 55-74
o Treatment
 Lumpectomy: surgical removal of a lump
 Mastectomy: surgical removal of breast tissue
 Radiation
 Chemotherapy
 Targeted Therapies

Question 21

• When does oogenesis begin?

Answer 21

o Oogenesis: production of female gametes – a parallel process to spermatogenesis
o Begins in the fetal period

Question 22

• At birth, a female infant has a lifetime supply of oocytes.

Answer 22

o At birth, a female infant is presumed to have a lifetime supply of primary oocytes (~2 million)

Question 23

• What does it mean to be the “dominant follicle?”

Answer 23

o From this small group, one primary oocyte is selected to become the dominant follicle
o The dominant follicle resumes meiosis I and creates 2 haploid cells – 1 secondary oocyte, 1st polar body

Question 24

• What cellular process happens during ovulation? What are the cellular products?

Question 25

* What is a polar body?

Question 26

* What happens if a secondary oocyte is fertilized? What will happen if it’s not?

Question 27

* Compare/contrast spermatogenesis and oogenesis. Be especially familiar with the net products (total number of functioning gametes) of each process.

Answer 27

o Similarities  Diploid Stem Cells  Divide by Mitosis  Primary Oo/Spermatocytes  Undergo meiosis I  Secondary Oo/Spermatocytes  Undergo Meiosis II  Ovum/Sperm o Differences  Oogenesis produces 1 viable ovum + 2/3 polar bodies * Unequal cell divisions ensure that the ovum has enough nutrients for a ~6-day journey to the uterus * Polar bodies degenerate and die  Spermatogenesis produces 4 viable sperm

Question 28

* How long is the typical ovarian cycle? What are the two phases? When does the ovulation event typically occur?

Answer 28

o A roughly ~28-day long series of events associated with the maturation of an egg o Cycle consists of 2 consecutive phases with ovulation occurring at midcycle - between the phases o Follicular Phase: Days 1-14; period of vesicular follicle growth o Luteal Phase: Days 14-28; period of corpus luteum activity o Only 10-15% of women have a 28-day cycle o Length of the follicular phase may vary, but length of the luteal phase is always 14 days – from ovulation to the end of the cycle

Question 29

* Define primordia follicle, primary follicle, secondary follicle, and vesicular follicle.

Answer 29

o Primordial Follicles: 1st follicles to develop in a female fetus o Primordial follicles become primary follicles through oocyte enlargement and a change in the shape of the surrounding cells – squamous to cuboidal o Primary follicles become secondary follicles when follicular cells proliferate to form stratified epithelium around the oocyte o Follicular cells are called granulosa cells when 1+ layer of cells is present o A secondary follicle becomes a vesicular follicle when a clear fluid-filled cavity called the antrum forms o A vesicular follicle bulges from the external ovary surface and is ready to be ovulated

Question 30

* Which hormone stimulates development of the follicles? From a hormonal perspective, what causes selection of the dominant follicle?

Answer 30

o During the follicular phase of the ovarian cycle, several vesicular follicles are stimulated to grow by rising levels of Follicle Stimulating Hormone (FSH) o FSH levels drop, and a dominant follicle is selected o The primary oocyte of the dominant follicle completes meiosis I and forms a secondary oocyte and a polar body o Granulosa cells signal for secondary oocyte to arrest at metaphase II

Question 31

* What hormone stimulates the rupturing of the ovarian wall?

Answer 31

o Rising levels of luteinizing hormone (LH) cause the ovary wall to rupture – the secondary oocyte is expelled into the peritoneal cavity o 1-2% of ovulations release more than one secondary oocyte – if fertilized, what would be the result?

Question 32

* Similar to you did for male reproduction, draw out the sequencing of hormones for triggering follicle development, ovulation, and development of the corpus luteum.

Question 33

* What hormone plays an additional role in inhibiting the reproductive cycles?

Question 34

* How are the uterine and ovarian cycles related?

Answer 34

o Uterine (Menstrual) Cycle: series of cyclic changes in the endometrium – changes occur in response to fluctuating ovarian hormone levels o Three Phases:  Days 1-5: menstrual phase  Days 6-14: proliferative (preovulatory) phase  Days 15-28: secretory (postovulatory) phase

Question 35

* What are the 3 phases of the uterine cycle? Define what happens in each phase. Especially note the role(s) of the ovarian hormones in each phase.

Answer 35

o Days 1-5: menstrual phase  Ovarian hormones are at their lowest levels  Gonadotropin levels begin to rise  Stratum functionalis detaches from the uterine wall and is shed – flow of menstrual blood and tissue lasts 3-5 days  By day 5, growing ovarian follicles start to produce more estrogen o Days 6-14: proliferative (preovulatory) 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 ~ day 14  o Days 15-28: 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

Question 36

* Define amenorrhea. What’s leptin? What role does it play?

Answer 36

o Extremely strenuous physical activity or very low levels of body fat can delay or stop menstruation in young female athletes o Amenorrhea: cessation of menstruation o Adipose cells help to covert adrenal androgens to estrogens and are a source of leptin o Leptin: hormone that plays a critical, permissive role in the onset of puberty o Once estrogen levels drop and the menstrual cycle stops, bone loss begins – can lead to osteoporosis o Amenorrhea in this context is typically reversible – but the bone loss may not be

Question 37

* What’s the role between estrogen and bone health? How about estrogen and cardiac health?

Answer 37

o Promote oogenesis and follicle growth in the ovaries o Exert anabolic effects on the female reproductive tract o Support rapid, short-lived growth spurts at puberty o Induce secondary sex characteristics o Growth of breasts and subcutaneous deposits of fat in the hips o Widening + lightening of pelvis o Metabolic effects: o Maintains low total blood cholesterol and high HDL levels o Facilitates calcium uptake and sustains bone density

Question 38

* Review the systemic effects of estrogen.

Question 39

* Recall the role of progesterone in maintaining pregnancy.

Answer 39

o Works with estrogen to establish and regulate the uterine cycle o Promotes changes in cervical mucus o Inhibits uterine motility during pregnancy o Prepares breasts for lactation

Question 40

* List some symptoms of declining levels of estrogen in women nearing menopause.

Answer 40

o Menopause: lack of menstruation for 1 year in females  Average Age at Menopause: 46 to 54 o There is no equivalent process in males o Symptoms of declining estrogen levels:  Atrophy of the reproductive organs and breasts  Irritability and depression  Hot flashes – intense vasodilation of the skin’s blood vessels  Gradual thinning of skin and bone loss  Increased total blood cholesterol levels and falling HDL o Pros + Cons of Hormone Replacement Therapy (HRT)

Question 41

* How is genetic sex determined? Which parent determines genetic sex of offspring? Be sure to understand the physiology of this!

Answer 41

o 23rd pair of chromosomes in a fertilized egg are the sex chromosomes o X chromosomes are large compared to Y chromosomes o XX: Female; XY: Male o Genetic sex is determined by sperm – why?

Question 42

* What is the SRY gene?

Answer 42

o SRY Gene: single gene on the Y chromosome that determines maleness by initiating development of testes

Question 43

* What’s a nondisjunction? Draw one out!

Answer 43

o Nondisjunction: abnormal distribution of any chromosomes to the gametes o Abnormal distribution of the sex chromosomes can cause abnormalities in the development of the reproductive systems