Bio 202 Female Reproductive System PDF

ARIZONA STATE UNIVERSITY Female College of Integrative Sciences & Arts Reproductive Bio 202 A natomy & Physiology II Tonya A. Penkrot, Ph.D. Figure 27.13 Organs of the female...

ARIZONA STATE UNIVERSITY Female College of Integrative Sciences & Arts Reproductive Bio 202 A natomy & Physiology II Tonya A. Penkrot, Ph.D. Figure 27.13 Organs of the female reproductive system, midsagittal section. Suspensory ligament of ovary Peritoneum Infundibulum Perimetrium Uterine tube Ovary Uterosacral Fimbriae ligament Uterus Rectouterine Round ligament pouch Vesicouterine pouch Rectum Urinary bladder Pubic symphysis Posterior fornix Mons pubis Cervix Urethra Anterior fornix Clitoris Vagina External urethral orifice Anus Hymen Urogenital diaphragm Labium minus Greater vestibular Labium majus gland Bio 202 A&P ASU DPC T. Penkrot © 2016 Pearson Education, Inc. Figure 27.14 Photomicrograph of a mammalian ovary showing follicles in different developmental phases. Tunica Germinal albuginea Cortex Medulla epithelium Primary follicles Secondary Antrum of follicle a vesicular (antral) follicle Bio 202 A&P ASU DPC T. Penkrot © 2016 Pearson Education, Inc. Figure 27.15a Internal female reproductive organs. Suspensory ligament of Uterine ovary (fallopian) tube Fundus Lumen of uterus Ovarian (cavity) blood vessels of uterus Uterine tube Broad ligament Ovary Ampulla Mesosalpinx Isthmus Infundibulum Mesovarium Mesometrium Fimbriae Ovarian Round ligament of uterus ligament Wall of uterus Body of uterus Endometrium Ureter Myometrium Uterine blood vessels Perimetrium Isthmus Internal os Uterosacral ligament Cervical canal Cardinal (lateral cervical) External os ligament Lateral fornix Vagina Cervix Posterior view Bio 202 A&P ASU DPC T. Penkrot © 2016 Pearson Education, Inc.  The Uterus (cont.)  Uterine wall Three layers of wall ― Perimetrium: outermost serous layer (visceral peritoneum) ― Myometrium: bulky middle layer consisting of interlacing layers of smooth muscle  Contracts rhythmically during childbirth ― Endometrium: mucosal lining  Simple columnar epithelium on top of a thick lamina propria  Fertilized egg burrows into endometrium and resides there during development Bio 202 A&P ASU DPC T. Penkrot © 2016 Pearson Education, Inc.  The Uterus (cont.)  Uterine wall (cont.) Endometrium has two chief layers (strata) ― Stratum functionalis (functional layer)  Changes in response to ovarian hormone cycles  Shed during menstruation ― Stratum basalis (basal layer)  Forms new stratum functionalis after menstruation  Unresponsive to ovarian hormones Bio 202 A&P ASU DPC T. Penkrot © 2016 Pearson Education, Inc. Figure 27.16a The endometrium and its blood supply. Lumen of uterus Epithelium Uterine glands Stratum functionalis of the endometrium Lamina propria (connective tissue) Stratum basalis of the endometrium Portion of the Smooth muscle myometrium fibers Bio 202 A&P ASU DPC T. Penkrot © 2016 Pearson Education, Inc. Figure 27.16b The endometrium and its blood supply. Lumen of uterus Epithelium Capillaries Uterine glands Venous sinusoids Lamina propria (connective tissue) Spiral (coiled) artery Straight artery Endometrial vein Radial artery Smooth muscle fibers Arcuate artery Uterine artery Bio 202 A&P ASU DPC T. Penkrot © 2016 Pearson Education, Inc.  Vagina  Thin-walled tube 8–10 cm (3–4 inches) in length  Functions as birth canal, passageway for menstrual flow, and organ of copulation  Extends between bladder and rectum from cervix to exterior  Urethra runs parallels to vagina anteriorly  Layers of wall Fibroelastic adventitia Smooth muscle muscularis Stratified squamous mucosa with rugae ― Dendritic cells in mucosa may provide route for HIV transmission Bio 202 A&P ASU DPC T. Penkrot © 2016 Pearson Education, Inc. Figure 27.13 Organs of the female reproductive system, midsagittal section. Suspensory ligament of ovary Peritoneum Infundibulum Perimetrium Uterine tube Ovary Uterosacral Fimbriae ligament Uterus Rectouterine Round ligament pouch Vesicouterine pouch Rectum Urinary bladder Pubic symphysis Posterior fornix Mons pubis Cervix Urethra Anterior fornix Clitoris Vagina External urethral orifice Anus Hymen Urogenital diaphragm Labium minus Greater vestibular Labium majus gland Bio 202 A&P ASU DPC T. Penkrot © 2016 Pearson Education, Inc. Figure 27.17b The external genitalia (vulva) of the female. Clitoris Labia minora Labia majora Anus Pubic symphysis Body of clitoris, Inferior containing pubic corpora ramus cavernosa Clitoris (glans) Crus of clitoris External urethral orifice Vaginal orifice Greater vestibular Bulb of gland vestibule Fourchette Bio 202 A&P ASU DPC T. Penkrot © 2016 Pearson Education, Inc.  27.11 Mammary Glands  Mammary glands are present in both male and female, but normally function only in female  Areola: pigmented skin surrounding nipple  Suspensory ligaments: attach breast to underlying muscle  Lobules within lobes contain glandular alveoli that produce milk Milk is passed into lactiferous ducts, then into lactiferous sinuses that open to outside at nipple In non-nursing women, glandular structure is undeveloped  Breast size is due to amount of fat deposits Bio 202 A&P ASU DPC T. Penkrot © 2016 Pearson Education, Inc. Figure 27.18 Structure of lactating mammary glands. First rib Skin (cut) Pectoralis major muscle Suspensory ligament Adipose tissue Lobe Areola Nipple Opening of lactiferous duct Lactiferous sinus Lactiferous duct Lobule containing alveoli Hypodermis (superficial fascia) Intercostal muscles Bio 202 A&P ASU DPC T. Penkrot © 2016 Pearson Education, Inc.  Breast Cancer  Invasive breast cancer is most common malignancy and second most common cause of cancer death in U.S. women  13% of women will develop condition  Usually arises from epithelial cells of smallest ducts that eventually metastasize  Risk factors Early onset of menstruation and late menopause No pregnancies or first pregnancy late in life No or short periods of breast feeding Family history of breast cancer Bio 202 A&P ASU DPC T. Penkrot © 2016 Pearson Education, Inc.  Breast Cancer (cont.)  70% of women with breast cancer have no known risk factors  10% due to hereditary defects, including mutations to genes BRCA1 and BRCA2 50% to 80% of women with these genes develop breast cancer Greater risk of ovarian cancer as well Bio 202 A&P ASU DPC T. Penkrot © 2016 Pearson Education, Inc.  Breast Cancer (cont.)  Treatment Depends upon characteristics of lesion ― Radiation, chemotherapy, or surgery often followed by radiation or chemotherapy to destroy stray cells ― Drugs for estrogen-responsive cancers  Trastuzumab (Herceptin): for aggressive cancer cells  Tamoxifen: improves outcome for premenopausal women with early- or late- stage cancer  Letrozole (Femara): reduces recurrence Bio 202 A&P ASU DPC T. Penkrot © 2016 Pearson Education, Inc.  27.12 Oogenesis  Oogenesis: production of female gametes takes years to complete  Begins in fetal period Oogonia (2n ovarian stem cells) multiply by mitosis and store nutrients Primary oocytes develop in primordial follicles that become surrounded by follicle cells Primary oocytes begin meiosis but stall in prophase I At birth, female presumed to have lifetime supply of primary oocytes Bio 202 A&P ASU DPC T. Penkrot © 2016 Pearson Education, Inc.  Oogenesis After Puberty  Each month after puberty, a few primary oocytes are activated  One from this group is “selected” each month to become dominant follicle that resumes meiosis I  After division of meisosis I is completed, two haploid cells of different sizes are produced: Secondary oocyte: large cell with almost all of mother cell cytoplasm and organelles First polar body: small cell almost devoid of cytoplasm Bio 202 A&P ASU DPC T. Penkrot © 2016 Pearson Education, Inc.  Oogenesis After Puberty (cont.)  Secondary oocyte arrests in metaphase II and becomes the ovulated ovum  If not penetrated by sperm, it deteriorates  If penetrated by sperm, second oocyte completes meiosis II, yielding: Ovum (functional gamete) Second polar body Bio 202 A&P ASU DPC T. Penkrot © 2016 Pearson Education, Inc. Figure 27.20 Events of oogenesis. Meiotic events Follicle development in ovary Before birth 2n Oogonium (stem cell) Follicle cells Mitosis Oocyte 2n Primary oocyte Primordial follicle Infancy and 2n Primary oocyte Primordial follicle childhood (arrested in prophase I; (ovary functionally present at birth) inactive) Each month from puberty to menopause Primary follicle 2n Primary oocyte (still arrested in prophase I) Secondary follicle Spindle Vesicular (antral) follicle Meiosis I (completed by one primary oocyte each month in response to LH surge) Secondary oocyte First polar body n (arrested in metaphase II) Ovulation Meiosis II of polar body (may or may not occur) Sperm Ovulated secondary oocyte Meiosis II completed Ruptured follicle (only if sperm becomes a corpus n n n n penetrates luteum and ultimately Polar bodies oocyte) degenerates. (all polar bodies Second Ovum degenerate) Degenerating polar body corpus luteum Bio 202 A&P ASU DPC T. Penkrot © 2016 Pearson Education, Inc.  27.13 The Ovarian Cycle  Ovarian cycle: monthly (~28 day) series of events associated with maturation of egg Two consecutive phases, with ovulation occurring midcycle between phases Follicular phase: period of vesicular follicle growth (days 1–14) Luteal phase: period of corpus luteum activity (days 14–28)  Only 10–15% women have 28-day cycle Follicular phase varies, but luteal phase is always 14 days from ovulation to end of cycle Bio 202 A&P ASU DPC T. Penkrot © 2016 Pearson Education, Inc. Figure 27.21 Schematic and microscopic views of the ovarian cycle: development and fate of ovarian follicles. 1 Primordial 2 Primary follicles follicle 3 Secondary follicle Theca folliculi 3 4a 4a Early vesicular 2 follicle Forming Theca antrum folliculi Primary oocyte 7 Zona pellucida Antrum Secondary oocyte 4b 6 5 Secondary oocyte 6 Corona radiata Zona pellucida Antrum 6 Corpus luteum (forms 5 Follicle ruptures; 4b Mature vesicular follicle carries from ruptured follicle) secondary oocyte ovulated out meiosis I; ready to be ovulated Bio 202 A&P ASU DPC T. Penkrot © 2016 Pearson Education, Inc.  Stages of Follicle Development (cont.)  Primary follicle becomes secondary follicle 3. Follicular cells proliferate, forming stratified epithelium around oocyte ― When more than one layer of cells are present:  Follicular cells now called granulosa cells  Primary follicle called secondary follicle Granulosa cells and oocyte guide one another’s development via gap junction connections Bio 202 A&P ASU DPC T. Penkrot © 2016 Pearson Education, Inc.  Stages of Follicle Development (cont.)  Secondary follicle becomes vesicular follicle Connective tissue and granulosa cells condense to form theca folliculi Zona pellucida: thick, glycoprotein-rich membrane secreted by oocyte, encapsulating it 4a. Early vesicular follicle formed when clear fluid begins to accumulate between granulosa cells 4b. Antrum: large cavity is formed when fluid coalesces ― Distinguishes vesicular follicle from previous follicles (pre-antral vs. antral) Bio 202 A&P ASU DPC T. Penkrot © 2016 Pearson Education, Inc.  Stages of Follicle Development (cont.)  Secondary follicle becomes vesicular follicle (cont.) Antrum continues to expand with fluid isolating oocyte ― Isolated oocyte with its surrounding granulosa cells called corona radiata Corona radiata sits on stalk on one side of follicle When follicle is full size (2.5 cm or 1 inch), it bulges from external ovary surface It is ready to be ovulated Bio 202 A&P ASU DPC T. Penkrot © 2016 Pearson Education, Inc.  Follicular Phase of the Ovarian Cycle  During follicular phase, several vesicular (antral) follicles are stimulated to grow Triggered by rising levels of FSH  FSH levels drop around middle of follicular phase Causes only one antral follicle, dominant follicle, to be selected to continue on How dominant follicle is chosen is still uncertain  Primary oocyte of dominant follicle completes meiosis I to form 2° oocyte and polar body  Granulosa cells then send signal to oocyte, causing it to stop at metaphase II Bio 202 A&P ASU DPC T. Penkrot © 2016 Pearson Education, Inc. Figure 27.20 Events of oogenesis. Meiotic events Follicle development in ovary Before birth 2n Oogonium (stem cell) Follicle cells Mitosis Oocyte 2n Primary oocyte Primordial follicle Infancy and 2n Primary oocyte Primordial follicle childhood (arrested in prophase I; (ovary functionally present at birth) inactive) Each month from puberty to menopause Primary follicle 2n Primary oocyte (still arrested in prophase I) Secondary follicle Spindle Vesicular (antral) follicle Meiosis I (completed by one primary oocyte each month in response to LH surge) Secondary oocyte First polar body n (arrested in metaphase II) Ovulation Meiosis II of polar body (may or may not occur) Sperm Ovulated secondary oocyte Meiosis II completed Ruptured follicle (only if sperm becomes a corpus n n n n penetrates luteum and ultimately Polar bodies oocyte) degenerates. (all polar bodies Second Ovum degenerate) Degenerating polar body corpus luteum Bio 202 A&P ASU DPC T. Penkrot © 2016 Pearson Education, Inc.  Ovulation  Rising levels of LH cause ovary wall to rupture, expelling secondary oocyte with its corona radiata to peritoneal cavity  Mittelschmerz: twinge of pain sometimes felt at ovulation by some women  1–2% of ovulations release more than one secondary oocyte, which, if fertilized, result in fraternal twins  Identical twins result from fertilization of one oocyte, then separation of daughter cells  If no pregnancy occurs, corpus luteum degenerates into corpus albicans (scar) in 10 days Luteolytic or ischemic phase: last 2–3 days of luteal phase, when endometrium begins to erode  If pregnancy occurs, corpus luteum produces hormones that sustain pregnancy until placenta takes over, at about 3 months Bio 202 A&P ASU DPC T. Penkrot © 2016 Pearson Education, Inc. Figure 27.22 Regulation of the ovarian cycle. Hypothalamus Hypothalamus GnRH 4 4 Positive feedback exerted GnRH by large in estrogen output by 6 Travels via maturing follicle. portal blood 1 Anterior pituitary 1 4 Progesterone LH surge Estrogens Inhibin FSH LH 5 Ruptured 2 2 follicle 6 Thecal cells 2 3 Slightly Androgens elevated 5 estrogen and rising inhibin Granulosa levels inhibit cells FSH secretion. 2 Inhibin Convert androgens Mature vesicular follicle Ovulated Corpus luteum to estrogens secondary oocyte 2 Estrogens Early and midfollicular phases Late follicular and luteal phases Bio 202 A&P ASU DPC T. Penkrot Stimulates Inhibits © 2016 Pearson Education, Inc.  Hormonal Regulation of Ovarian Cycle (cont.) Negative feedback inhibits gonadotropin release ― Increasing levels of plasma estrogen levels exert negative feedback inhibition on FSH and LH release ― Inhibin from granulosa cells also inhibits FSH release ― Only dominant follicle can withstand this dip in FSH  Other developing follicles deteriorate Bio 202 A&P ASU DPC T. Penkrot © 2016 Pearson Education, Inc.  The Uterine (Menstrual) Cycle  Uterine (menstrual) cycle: cyclic series of changes in endometrium that occur in response to fluctuating ovarian hormone levels  Three phases: 1. Days 1–5: menstrual phase 2. Days 6–14: proliferative (preovulatory) phase 3. Days 15–28: secretory (postovulatory) phase Bio 202 A&P ASU DPC T. Penkrot © 2016 Pearson Education, Inc. Figure 27.23a Correlation of anterior pituitary and ovarian hormones with structural changes of the ovary and uterus. Plasma hormone level LH FSH Fluctuation of gonadotropin levels: Fluctuating levels of pituitary gonadotropins (follicle-stimulating hormone and luteinizing hormone) in the blood regulate the events of the ovarian cycle. Bio 202 A&P ASU DPC T. Penkrot © 2016 Pearson Education, Inc. Figure 27.23b Correlation of anterior pituitary and ovarian hormones with structural changes of the ovary and uterus. Ovulation Corpus Degenerating luteum corpus luteum Dominant follicle Follicular Luteal Ovulation phase phase (Day 14) Ovarian cycle: Structural changes in vesicular ovarian follicles and the corpus luteum are correlated with changes in the endometrium of the uterus during the uterine cycle (d). Recall that only vesicular follicles (in their antral phase) are hormone dependent—primary and secondary follicles are not. Bio 202 A&P ASU DPC T. Penkrot © 2016 Pearson Education, Inc. Figure 27.23c Correlation of anterior pituitary and ovarian hormones with structural changes of the ovary and uterus. Plasma hormone level Estrogens Progesterone Fluctuation of ovarian hormone levels: Fluctuating levels of ovarian hormones (estrogens and progesterone) cause the endometrial changes of the uterine cycle. The high estrogen levels are also responsible for the LH/FSH surge in (a). Bio 202 A&P ASU DPC T. Penkrot © 2016 Pearson Education, Inc. Figure 27.23d Correlation of anterior pituitary and ovarian hormones with structural changes of the ovary and uterus. Endometrial Blood vessels glands Menstrual flow Functional layer Basal layer Days 1 5 10 15 20 25 28 Menstrual Proliferative Secretory phase phase phase The three phases of the uterine cycle: Menstrual: The functional layer of the endometrium is shed. Proliferative: The functional layer of the endometrium is rebuilt. Secretory: Begins immediately after ovulation. Enrichment of the blood supply and glandular secretion of nutrients prepare the endometrium to receive an embryo. Both the menstrual and proliferative phases occur before ovulation, and together they correspond to the follicular phase of the ovarian cycle. The secretory phase corresponds in time to the luteal phase of the ovarian cycle. Bio 202 A&P ASU DPC T. Penkrot © 2016 Pearson Education, Inc. Figure 27.23 Correlation of anterior pituitary and ovarian hormones with structural changes of the ovary Fluctuation of gonadotropin levels: and uterus. Fluctuating levels of pituitary gonadotropins (follicle-stimulating hormone and luteinizing hormone) in the blood regulate the events of the ovarian cycle. Plasma hormone level LH FSH Ovulation Corpus Degenerating Ovarian cycle: Structural changes in luteum corpus luteum vesicular ovarian follicles and the corpus Dominant luteum are correlated with changes in the follicle endometrium of the uterus during the uterine cycle (d). Recall that only vesicular follicles (in their antral phase) are hormone dependent —primary and secondary follicles are not. Follicular Ovulation Luteal phase (Day 14) phase Fluctuation of ovarian hormone levels: Plasma hormone level Fluctuating levels of ovarian hormones (estrogens and progesterone) cause the endometrial changes of the uterine cycle. The high estrogen levels are also responsible for the LH/FSH surge in (a). Estrogens Progesterone Endometrial Blood vessels The three phases of the uterine cycle: glands Menstrual: The functional layer of the endometrium is shed. Proliferative: The functional layer of the endometrium is rebuilt. Secretory: Begins immediately after ovulation. Menstrual Enrichment of the blood supply and glandular flow secretion of nutrients prepare the endometrium Functional to receive an embryo. layer Both the menstrual and proliferative phases occur before Basal layer ovulation, and together they correspond to the follicular Days 1 5 10 15 20 25 28 phase of the ovarian cycle. The secretory phase corresponds Menstrual Proliferative Secretory in time to the luteal phase of the ovarian cycle. Bio 202 A&P ASU DPC T. Penkrot phase phase phase © 2016 Pearson Education, Inc.  Effects of Estrogens and Progesterones  Estrogens: Promote oogenesis and follicle growth in ovary Exert anabolic effect on female reproductive tract Support rapid short-lived growth spurts at puberty Induce secondary sex characteristics ― Growth of breasts ― Increased deposit of subcutaneous fat (hips and breasts) ― Widening and lightening of pelvis Estrogen also has metabolic effects: ― Maintains low total blood cholesterol and high HDL levels ― Facilitates calcium uptake Bio 202 A&P ASU DPC T. Penkrot © 2016 Pearson Education, Inc. Effects of Estrogens and Progesterones (cont.)  Progesterone works with estrogen to establish and regulate uterine cycle Promotes changes in cervical mucus Effects of placental progesterone during pregnancy ― Inhibits uterine motility ― Helps prepare breasts for lactation Bio 202 A&P ASU DPC T. Penkrot © 2016 Pearson Education, Inc. Figure 27.24-1 Development of the internal reproductive organs. Mesonephric Mesonephros (Wolffian) duct Gonadal ridge Paramesonephric (Müllerian) duct Metanephros (kidney) Cloaca SRY SRY 5- to 6-week embryo: sexually indifferent stage Bio 202 A&P ASU DPC T. Penkrot © 2016 Pearson Education, Inc. Figure 27.24-2 Development of the internal reproductive organs. Testes Efferent ductules Epididymis Paramesonephric duct (degenerating) Mesonephric duct forming the ductus deferens Urinary bladder Seminal gland Urogenital sinus forming the urethra 7- to 8-week male Bio 202 A&P ASU DPC T. Penkrot © 2016 Pearson Education, Inc. Figure 27.24-3 Development of the internal reproductive organs. Ovaries Paramesonephric duct forming the uterine tube Mesonephric duct (degenerating) Fused paramesonephric ducts forming the uterus Urinary bladder (moved aside) Urogenital sinus forming the urethra and lower vagina 8- to 9-week female Bio 202 A&P ASU DPC T. Penkrot © 2016 Pearson Education, Inc. Figure 27.24-4 Development of the internal reproductive organs. Urinary bladder Seminal gland Prostate Bulbo-urethral gland Ductus deferens Urethra Efferent ductules Epididymis Testis Penis At birth: male development Bio 202 A&P ASU DPC T. Penkrot © 2016 Pearson Education, Inc. Figure 27.24-5 Development of the internal reproductive organs. Uterine tube Ovary Uterus Urinary bladder (moved aside) Vagina Urethra Hymen Vestibule At birth: Female development Bio 202 A&P ASU DPC T. Penkrot © 2016 Pearson Education, Inc. Figure 27.25 Development of homologous structures of the external genitalia in both sexes. Urethral fold Genital tubercle Labioscrotal swelling Anus Urethral groove Tail (cut) Sexually indifferent stage Approximately 5 weeks Glans penis Glans clitoris Urogenital Labioscrotal Urethral sinus Labioscrotal swellings folds swellings Urethral (scrotum) (labia majora) folds (labia Anus Anus minora) Glans penis Glans clitoris Penis Scrotum Labia majora Anus Labia Anus minora Male development Female development Bio 202 A&P ASU DPC T. Penkrot © 2016 Pearson Education, Inc.