Overview of Reproductive System Anatomy

Title: Microsoft PowerPoint - Lecture 24 Reproductive Covid-19 URL Source: blob://pdf/87cd36a9-b68a-43a9-9b25-f4b7cb6aafbe Markdown Content: Anatomy of Reproductive System Gonads : organs that produce gametes and hormones gametes : sperms & ova Ducts : receive and transport gametes Accessory glands : secrete fluids into ducts External genitalia : perineal structures Types of Reproductive System ## Male reproductive system ## Female reproductive system Male Reproductive System Major Structures of the Male Reproductive System Ducts Gonad External Genitalia Prostatic urethra Pubic symphysis Ejaculatory duct Membranous urethra Spongy urethra Ductus deferens Epididymis Testis Penis Scrotum Urinary bladder Ureter Seminal gland Rectum Prostate gland External urethral orifice Anus Accessory Glands Corpus spongiosum Corpus cavernosum Bulbourethral gland Anatomy of Male Reproductive System Gonads : testes Ducts : epididymis, vas (ductus) deferens, ejaculatory duct, urethra Accessory glands : seminal vesicles, prostate, bulbourethral glands External genitalia : scrotum, penis Anterior View of Male Reproductive System: Spermatic Cord Urinary bladder Spermatic Cord Inguinal canal Ductus deferens Genitofemoral nerve Deferential artery Pampiniform plexus Testicular artery Epididymis Scrotal cavity Testis (covered by visceral layer of tunica vaginalis) Parietal layer of tunica vaginalis (inner lining of cremaster, facing scrotal cavity) Raphe Testicular artery Testicular vein Penis Inguinal ligament Superficial inguinal ring Spermatic cord Scrotal septum Cremaster muscle with cremasteric fascia Superficial scrotal fascia Dartos muscle Scrotal skin (cut) Layers of the Scrotum Spermatic Cord Fibromuscular tube: consists of layers of fascia and smooth muscle Extends between abdominopelvic cavity and testis Encloses: vas deferens testicular vessels, lymphatics, and nerves Passes through inguinal canal > Spermatic Cord > Inguinal > canal > Ductus deferens > Genitofemoral nerve > Deferential artery > Pampiniform plexus > Testicular artery Inguinal Canals Passageways through abdominal musculature Form during development as testes descend into scrotum Inguinal Hernia Protrusion of visceral tissues into inguinal canal through a defect in the wall Types: Male Reproductive System Gonads : testes Ducts: epididymis, vas (ductus) deferens, ejaculatory duct, urethra Accessory glands: seminal vesicles, prostate, bulbourethral glands External genitalia: scrotum, penis Testes Egg-shaped (5L X 3W X 2.5T cm) Weight: 1015 g Hang in scrotum : normal sperm development in testes requires temperatures 1C < body temperature Function: produce male gametes ( spermatozoa = sperms): > 1/2 billion sperms / day secrete male sex hormones ( androgens )Formation & Descent of the Testes Testes form inside the abdominal cavity adjacent to kidneys Descend through abdominal cavity Reach the scrotum at birth > Peritoneum > Gubernaculum > testis > Testis > Colon > 2 months > 5 mm > Umbilical > cord > Penis > 3 months > 5 mm > 5 mm > Birth > Scrotum > Testis > Pubis > Testis Structure of the Testes Ductus deferens Epididymis Efferent ductule Skin Scrotum Dartos muscle Superficial scrotal fascia Cremaster muscle Tunica vaginalis Tunica albuginea Scrotal cavity Septa Lobule Raphe Septa Seminiferous tubules Straight tubule Rete testis Mediastinum of testis Testis A section through a testis LM 26 Covering of the Testis Scrotum : skin: dartos muscle: smooth muscle in dermis superficial fascia (subcutaneous tissue) Cremaster muscle : skeletal muscle layer deep to the scrotum Tunica vaginalis : serous membrane lines scrotal cavity visceral & parietal layers with a cavity Tunica albuginea > Ductus deferens > Epididymis > Efferent ductule > Skin Scrotum > Dartos muscle > Superficial > scrotal fascia > Cremaster muscle > Tunica vaginalis > Tunica albuginea > Scrotal cavity > Septa > Lobule 1 2 3 4 5 6Tunica Albuginea Dense connective tissue layer covers the testis Continuous with fibers surrounding epididymis Extends into substance of testis form fibrous partitions ( septa ) divide testis into lobules > Ductus deferens > Epididymis > Efferent ductule > Skin Scrotum > Dartos muscle > Superficial > scrotal fascia > Cremaster muscle > Tunica vaginalis > Tunica albuginea > Scrotal cavity > Septa > Lobule Testicular Lobules Each testis contains 250-400 lobules Each lobule contains 1-3 slender tightly- coiled seminiferous tubules Ductus deferens Epididymis Efferent ductule Skin Scrotum Dartos muscle Superficial scrotal fascia Cremaster muscle Tunica vaginalis Tunica albuginea Scrotal cavity Septa Lobule Seminiferous Tubules Sperm factory Testis contains about 1/2 mile of tightly-coiled seminiferous tubules Each seminiferous tubule: 80 cm long forms a loop connected to rete testis : > a network of passageways > Seminiferous > tubules > Straight > tubule > Rete > testis ## Seminiferous Tubules Interstitial Cells (of Leydig) Located in connective tissue capsules surround seminiferous tubules Produce androgens : > e.g., testosterone Sustentacular (Sertoli, Nurse) Cells Extend from tubular capsule to lumen of seminiferous tubules Function: support spermatogenesis : > under effect of FSH and testosterone secretory function : > e.g., inhibin hormone and androgen binding protein maintain bloodtestis barrier : > isolates seminiferous tubules through tight junctions Spermatogenesis Process of sperms production Begins at puberty In seminiferous tubules: begins at outermost cell layer proceeds toward lumen 3 integrated processes: mitosis meiosis spermiogenesis Spermatogenesis Mitosis of spermatogonium Meiosis I Meiosis II Spermiogenesis (physical maturation) Primary spermatocyte (diploid, 2n) DNA replication Primary spermatocyte Synapsis and tetrad formation Secondary spermatocytes Spermatids (haploid, n) Spermatozoa (haploid, n) 46 46 92 46 23 23 Steps of Spermatogenesis Mitosis: spermatogonia (stem cells) 2 daughter cells: > 1 remains as spermatogonium > second differentiates into primary spermatocyte DNA replication Meosis: Meosis I : primary spermatocytes secondary spermatocytes Meosis II : secondary spermatocytes spermatids Spermiogenesis: spermatids (immature) spermatozoa (mature): > lose contact with wall of seminiferous tubule > enter lumen (= spermiation) Meiosis produces gametes that contain 1/2 of chromosomes in somatic cells For each cell entering meiosis: testes produce 4 spermatozoa ovaries produce 1 ovum and 3 polar bodies Cells & Meiosis Structure of a Spermatozoon Head : contains nucleus and chromosomes has an acrosomal cap at tip: > contains enzymes for fertilization Neck : contains centrioles Middle piece : contains mitochondria Tail (flagellum ): whip-like organelle to move the sperm Sperm Maturation Testes produce sperms that are: physically mature functionally immature Other parts of reproductive system are responsible for: functional maturation, nourishment, storage, and transport Male Reproductive System Gonads: testes Ducts : epididymis, vas (ductus) deferens, ejaculatory duct, urethra Accessory glands: seminal vesicles, prostate, bulbourethral glands External genitalia: scrotum, penis Epididymis Vas (ductus ) deferens Ejaculatory duct Urethra Ducts Prostatic urethra Pubic symphysis Ejaculatory duct Membranous urethra Spongy urethra Ductus deferens Epididymis Testis Penis Scrotum Urinary bladder External urethral orifice Corpus spongiosum Corpus cavernosum Ducts (Passageways of Spermatozoa) Efferent Ductules 1520 large efferent ductules : connect rete testis to epididymis > Ductus deferens > Epididymis > Efferent ductule > Straight > tubule > Rete > testis Epididymis Start of passageways of sperms Coiled tube almost 7 m long: bound to posterior border of testis Parts: head : > proximal to the testis body : > at posterior margin of testis tail : > near inferior border of testis > primary storage location of sperms Functions of the Epididymis Functional maturation of spermatozoa Stores spermatozoa Recycles damaged spermatozoa Monitors and adjusts fluid produced by seminiferous tubules Vas (Ductus) Deferens Ureter Ductus deferens Seminal gland Ampulla of ductus deferens Duct of seminal gland Ejaculatory duct Prostate gland Prostatic urethra A posterior view of the urinary bladder and prostate gland, showing subdivisions of the ductus deferens in relation to surrounding structures. Connective tissue and smooth muscle Prostatic (tubuloalveolar) glands Histological detail of the glands of the prostate. The tissue between the individual glandular units consists largely of smooth muscle. Contractions of this muscle tissue help move the secretions into the ejaculatory duct and urethra. Histology of the bulbourethral glands, which secrete a thick mucus into the spongy urethra. Histology of the seminal glands. These organs produce most of the volume of seminal fluid. Light micrograph showing the thick layers of smooth muscle in the wall of the ductus deferens. Lumen of ductus deferens Smooth muscle Lumen Secretory pockets Smooth muscle Bulbourethral glands Urogenital diaphragm Smooth muscle Capsule Mucous glands Ductus deferens LM 120 Seminal gland LM 45 Bulbourethral gland LM 175 Prostate gland LM 50 Urinary bladder c d a b e Lumen Vas Deferens 3045 cm long cord Begins at tail of the epididymis Ascends through inguinal canal: > within the spermatic cord Curves inferiorly along urinary bladder Lumen enlarges at the end into ampulla Opens in the ejaculatory duct Can store sperms for several months Structure of Vas Deferens Lined by pseudostratified columnar ciliated epithelium Wall contains thick smooth muscle layer : inner & outer longitudinal middle circular peristaltic contractions propel spermatozoa and fluid > Lumen of ductus > deferens > Smooth > muscle Stereocilia = non motile cilia Vasectomy Surgical cut of the 2 vasa deferentia Effective method of contraception Comparable to tubal ligation in females Ejaculatory Duct Short passageway (2 cm) at junction of ampulla and seminal vesicle duct Penetrates wall of prostate gland Empties into urethra Male Urethra 1820 cm long Extends from bladder neck to tip of penis Divided into 3 parts: prostatic urethra : passes through center of prostate gland membranous urethra : short segment that penetrates the urogenital diaphragm spongy (penile ) urethra : from urogenital diaphragm to external urethral orifice > Prostatic urethra > Ejaculatory duct > Membranous urethra > Spongy urethra > Ductus deferens > Epididymis > Testis > Penis > Urinary bladder > Ureter > Rectum Male Reproductive System Gonads: testes Ducts: epididymis, vas (ductus) deferens, ejaculatory duct, urethra Accessory glands : seminal vesicles, prostate, bulbourethral glands External genitalia: scrotum, penis Accessory Glands Seminal vesicles Prostate Bulbourethral glands Secrete fluids into ejaculatory ducts & urethra Seminal gland Duct of seminal gland Ejaculatory duct Prostate gland Prostatic urethra Bulbourethral glands Urogenital diaphragm > Urinary > bladder Seminal Fluid Mixture of secretions from accessory glands: each with distinctive biochemical characteristics contains enzymes: e.g., protease, fibrinolysin Function: activates spermatozoa provides nutrients for spermatozoa produces buffers to counteract acidity of urethra and vagina facilitates movement of spermatozoa Seminal Vesicles 2 tubular glands: coiled and folded 5 X 2.5 cm Produce about 60% of seminal fluid > Lumen > Secretory > pockets > Smooth > muscle Vesicular Fluid Composition: fructose : for nutrition prostaglandins : stimulate smooth muscle contractions (male and female) fibrinogen : forms temporary clot in vagina Slightly alkaline Has same osmotic concentration as plasma Discharged into ejaculatory duct Compound tubuloalveolar gland Surrounded by smooth muscle fibers 4 cm in diameter Encircles proximal portion of urethra: below urinary bladder Produces 20-30% of seminal fluid Prostate Connective tissue and smooth muscle > Prostatic glands Prostatic Fluid Slightly acidic Contains antibiotic seminalplasmin Ejected into prostatic urethra Bulbourethral (Cowpers) Glands 2 compound tubuloalveolar mucous glands Round shaped 1 cm in diameter Located at base of penis Empty into urethral lumen > Smooth > muscle > Capsule > Mucous > glands > Lumen Bulbourethral Secretion Thick mucus Alkaline Function: Neutralizes acids in urethra and vagina lubricates the glans Semen Semen = spermatozoa + seminal fluid Volume (= ejaculate ): typical ejaculation releases 25 ml low volume may indicate problems with prostate or seminal vesicles Sperm Count Normal range: 20100 million spermatozoa/ml of ejaculate > SEM 780 Semen Analysis Volume pH Sperm count Morphology Motility Male Reproductive System Gonads: testes Ducts: epididymis, vas (ductus) deferens, ejaculatory duct, urethra Accessory glands: seminal vesicles, prostate, bulbourethral glands External genitalia : scrotum, penis External Genitalia Scrotum : fleshy pouch encloses testes Penis : erectile organ contains distal portion of urethra Scrotum Divided into 2 chambers ( scrotal cavities ) Each testis lies in a separate chamber Structure: skin: > dartos muscle : in the dermis superficial fascia (subcutaneous tissue) > Skin > Scrotum > Dartos muscle > Superficial > scrotal fascia Penis Tubular organ: through which distal portion of urethra passes Function: conducts urine to exterior introduces semen into female vagina Regions of the Penis Root : fixed portion of penis attaches penis to body wall Shaft : movable portion of the penis contains erectile tissue Neck : narrow portion between shaft and glans Glans : expanded distal end of penis: > surrounds external urethral orifice Prepuce (Foreskin) Fold of skin surrounding tip of penis Attaches to neck and continues over glans Preputial glands : small glands at the base of the glans secrete smegma : > waxy material > support bacterial growth Circumcision Surgical removal of the prepuce Erectile Tissue In shaft of penis Contains network of vascular channels: incompletely separated by partitions of elastic connective tissue and smooth muscle fibers 3 cylindrical columns: 2 corpora cavernosa 1 corpus spongiosum Corpora Cavernosa 2 cylindrical masses of erectile tissue: under anterior surface of flaccid penis encircled by dense collagenous sheath each surrounds a central artery Diverge at their bases: forming crura of penis: > each crus is bound to ramus of ischium and pubis: > by tough connective-tissue ligaments > Right crus > of penis Corpus Spongiosum Surrounds penile urethra Relatively slender Expands to form the glans Surrounded by a sheath: with more elastic fibers than corpora cavernosa Erectile tissue contains a pair of small arteries Erectile Function Resting state (flaccid penis): arterial branches are constricted muscular partitions are tense blood flow into erectile tissue is restricted Erection (penis stiffens): arterial dilation increased blood flow assumes more upright position Male reproductive function is regulated by the complex interaction of hormones from the hypothalamus, anterior lobe of the pituitary gland, and the testes. Negative feedback systems keep testosterone levels within a relatively narrow range until late in life. Release of Gonadotropin- Releasing Hormone (GnRH) The hypothalamus secretes the hormone GnRH at a rate that remains relatively steady. As a result, blood levels of FSH, LH, and testosterone remain within a relatively narrow range throughout a mans reproductive life. High testosterone levels inhibit the release of GnRH by the hypothalamus, causing a decrease in LH secretion, which lowers testosterone to normal levels. Negative feedback When stimulated by GnRH, the anterior lobe of the pituitary gland releases luteinizing hormone (LH) and follicle- stimulating hormone (FSH). Inhibin depresses the pituitary production of FSH, and perhaps the hypothalamic secretion of gonadotropin-releasing hormone (GnRH).The faster the rate of sperm production, the more inhibin is secreted. By regulating FSH and GnRH secretion, nurse cells provide feedback control of spermatogenesis. Secretion of Follicle- Stimulating Hormone (FSH) FSH targets primarily the nurse cells of the seminiferous tubules. Secretion of Luteinizing Hormone (LH) LH targets the interstitial cells of the testes. Interstitial Cell Stimulation LH induces the secretion of testosterone and other androgens by the interstitial cells of the testes. Nurse Cell Stimulation Under FSH stimulation, and with testosterone from the interstitial cells, nurse cells (1) secrete inhibin in response to factors released by developing spermatozoa, (2) secrete androgen-binding protein (ABP), and (3) promote spermatogenesis and spermiogenesis. > Negative feedback Inhibin Testosterone Peripheral Effects of Testosterone Androgen-binding protein (ABP) binds androgens within the seminiferous tubules, which increases the local concentration of androgens and stimulates the physical maturation of spermatids. Nurse cell environment facilitates both spermatogenesis and spermiogenesis. Maintains libido (sexual drive) and related behaviors Stimulates bone and muscle growth Establishes and maintains male secondary sex characteristics Maintains accessory glands and organs of the male reproductive system KEY Stimulation Inhibition HYPOTHALAMUS ANTERIOR LOBE OF THE PITUITARY GLAND TESTES ? Hormonal Regulation of Male Reproductive Function Functions of Testosterone Stimulates spermatogenesis Maintains male reproductive organs Establishes male secondary sex characters : hair distribution, deep voice, muscle mass, adipose tissue deposits, Enhances libido and related behaviors Stimulates metabolism : e.g. protein synthesis - muscle and bone growth blood cell formation Estradiol Produced in small amounts by: gonads : > 70%: converted from circulating testosterone by aromatase enzyme > 30%: secreted by interstitial and sustentacular cells of testes adrenal cortex : > zona reticularis Rectouterine pouch Vesicouterine pouch Urinary bladder Urethra Pubic symphysis Accessory Glands Paraurethral glands Greater vestibular gland Clitoris Ovarian follicle Sigmoid colon Rectum Anus Major Structures of the Female Reproductive System Ovary Uterine tube Uterus Vagina External Genitalia Perimetrium Myometrium Endometrium Cervix Labium minus Labium majus ## Female Reproductive System Anatomy of Female Reproductive System Gonads : ovaries Ducts : uterine (Fallopian) tubes, uterus, vagina Accessory glands : release secretions into female reproductive tract mammary glands External genitalia : vulva Function of Female Reproductive System > Produces sex hormones and functional gametes > Protects and supports developing embryo > Nourishes newborn infant Structural Support Ovarian artery and vein Fimbriae Uterine tube Suspensory ligament Infundibulum Ovary Ureter Uterosacral ligament External os Cervix Vaginal rugae Vaginal wall Uterus Broad ligament Ovarian ligament Mesovarium Suspensory ligament Retractor Structures Stabilizing the Ovary Broad ligament : encloses ovaries, uterine tubes, and uterus Broad Ligament Continuation of parietal peritoneum Connects reproductive organs to the walls and floor of the pelvis Subdivides peritoneal cavity into: rectouterine pouch : > between uterus and rectum vesicouterine pouch : > between uterus and bladder Broad Ligament Continuation of parietal peritoneum Connects reproductive organs to the walls and floor of the pelvis Subdivides peritoneal cavity into: rectouterine pouch : > between uterus and rectum vesicouterine pouch : > between uterus and bladder > Vesicouterine > pouch Divisions of Broad Ligament Mesometrium : mesentery of the uterus largest portion Mesosalpinx : surrounds each uterine tube Mesovarium : surrounds and stabilizes each ovary Female Reproductive System Gonads : ovaries Ducts: uterine tubes, uterus, vagina Accessory glands: release secretions into female reproductive tract mammary glands External genitalia: vulva Ovaries > Uterine > tube > Corpus > luteum > Cortex > Tunica > albuginea > Mature > follicle > Germinal > epithelium > Egg > nest > Ovarian > hilum > Broad ligament > Mesovarium > Mesosalpinx > Mesenteries of > the Ovary and > Uterine Tube Almond-shaped organs 5L X 2.5W X 0.8T cm Weight: 68 g Near lateral walls of pelvic cavity Function: produce female gametes ( ova or oocytes) secrete female sex hormones ( estrogens and progestins )Ovarian Support Mesovarium Ovarian ligament : extends from uterus to ovary Suspensory ligament : extends from ovary to pelvic wall contains ovarian artery and vein > Uterus > Broad ligament > Ovarian > ligament > Mesovarium Suspensory > ligament Retractor > Structures Stabilizing the Ovary Covering of The Ovary Germinal epithelium : outer layer of visceral peritoneum consists of columnar epithelial cells Tunica albuginea : inner layer of connective tissue > Cortex > Tunica > albuginea > Mature > follicle > Germinal > epithelium > Egg > nest > Ovarian > hilum > Medulla Structure of The Ovary Superficial cortex : contains: ovarian follicles stroma: CT Deep medulla contains blood vessels, lymphatics, and nerves > Cortex > Tunica > albuginea > Mature > follicle > Germinal > epithelium > Egg > nest > Ovarian > hilum > Medulla Oogenesis Process of ova production Begins before birth Accelerates at puberty Ends at menopause 2 processes: mitosis meiosis Oogenesis Mitosis of oogonium Meiosis I Meiosis II Oogonium Oogonium (stem cell) Primary oocyte (diploid, 2n) DNA replication Primary oocyte Tetrad First polar body Secondary oocyte First polar body may not complete meiosis II Secondary oocyte released (ovulation) in metaphase of meiosis II Second polar body Nucleus of oocyte (n) Sperm (n) Fertilization (see Figure 291) 46 46 92 46 23 Process of Oogenesis: Female Fetal Development Oogonia (stem cells ): complete mitotic divisions before birth Between third and seventh months of intrauterine life: primary oocytes : > prepare for meiosis > stop at prophase of meiosis I > remain in suspended development till puberty Process of Oogenesis: Puberty Rising FSH triggers start of ovarian cycle Each month thereafter: some primary oocytes are stimulated to develop secondary oocytes (stop in metaphase II until fertilization) if fertilization occurs meosis II is completed ovum Steps of Oogenesis: Summary Oogonium (mitosis ) primary oocyte Primary oocyte (meiosis I ) first polar body [discarded] + secondary oocyte Secondary oocyte (meiosis II ) second polar body [discarded] + ovum Meiosis produces gametes that contain 1/2 of chromosomes in somatic cells For each cell entering meiosis: testes produce 4 spermatozoa ovaries produce 1 ovum and 3 polar bodies Cells & Meiosis Spermatogenesis Mitosis of spermatogonium Each division of a diploid spermatogonium produces two daughter cells. One is a spermatogonium that remains in contact with the basement membrane of the tubule, and the other is a primary spermatocyte that is displaced toward the lumen. These events from spermatogonium to primary spermatocyte take 16 days. Meiosis I Meiosis II Spermiogenesis (physical maturation) As meiosis I begins, each primary spermatocyte contains 46 individual chromosomes. At the end of meiosis I, the daughter cells are called secondary spermatocytes. Every secondary spermatocyte contains 23 chromosomes, each with a pair of duplicate chromatids. This phase of spermatogenesis takes about 24 days. The secondary spermatocytes soon enter meiosis II, which yields four haploid spermatids , each containing 23 chromosomes. For each primary spermatocyte that enters meiosis, four spermatids are produced. This phase lasts only a few hours. In spermiogenesis, the last step of spermatogenesis, each spermatid matures into a single spermatozoon, or sperm. The process of spermiogenesisfrom spermatids to spermatozoatakes 24 days. Primary spermatocyte (diploid, 2n) DNA replication Primary spermatocyte Synapsis and tetrad formation Secondary spermatocytes Spermatids (haploid, n) Spermatozoa (haploid, n) Oogenesis Mitosis of oogonium Unlike spermatogonia, the oogonia (--G-n-uh), or female reproductive stem cells, complete their mitotic divisions before birth. Meiosis I Between the third and seventh months of fetal development, the daughter cells, or primary oocytes (--sts), prepare to undergo meiosis. They proceed as far as the prophase of meiosis I, but then the process comes to a halt. The primary oocytes remain in a state of suspended development until puberty, when rising levels of FSH trigger the start of the ovarian cycle. Each month after the ovarian cycle begins, some of the primary oocytes are stimulated to undergo further development. Meiosis I is then completed, yielding a secondary oocyte and a polar body. Meiosis II Each month after the ovarian cycle begins, one or more secondary oocytes leave the ovary suspended in metaphase of meiosis II. At the time of fertilization, a second polar body forms and the fertilized oocyte is then called a mature ovum. (A cell in any of the preceding steps in oogenesis is sometimes called an immature ovum.) Oogonium Oogonium (stem cell) Primary oocyte (diploid, 2n) DNA replication Primary oocyte Tetrad First polar body Secondary oocyte First polar body may not complete meiosis II Secondary oocyte released (ovulation) in metaphase of meiosis II Second polar body Nucleus of oocyte (n) Sperm (n) Fertilization Ovarian Follicle Basic unit of female reproductive biology Located in cortex of ovaries Passes through different phases of maturation Composition depends on degree of maturation Structure of Mature (Graafian) Follicle Secondary oocyte Antrum Granulosa cells Corona radiata LM 136 Structure of Mature (Graafian) Follicle 1. Secondary oocyte 2. Granulosa cells 3. Corona radiata: > granulosa cells surround oocyte 4. Zona pellucida: > glycoprotein layer around oocyte 5. Theca cells: > interna and externa > secrete androgen and estrogen 6. Antrum: > contains follicular fluid > 1 > 6 > 2 > 3 > 5 > 4 Ovarian Follicle Atresia Degeneration of primordial follicles Ovaries have about 2 million primordial follicles at birth: each contains a primary oocyte By puberty: number drops to about 400,000 Ovarian Cycle Monthly oogenesis : between puberty and menopause After sexual maturation: a different group of primordial follicles is activated each month Divided into: follicular phase (preovulatory phase) luteal phase (postovulatory phase) Steps of Ovarian Cycle Corpus Luteum Ovarian follicle after ovulation Produces progestins (progesterone ): prepares uterus for pregnancy If fertilization does not occur : degenerates about 12 days after ovulation fills with scar tissue to become corpus albicans > Corpus luteum Corpus albicans Female Reproductive System Gonads: ovaries Ducts : uterine tubes, uterus, vagina Accessory glands: release secretions into female reproductive tract mammary glands External genitalia: vulva Uterine (Fallopian) Tubes Ampulla Isthmus Fimbriae Uterus Infundibulum Microvilli of mucin- secreting cells Cilia Epithelial surface SEM 4000 Isthmus Smooth muscle Lamina propria Columnar epithelium A sectional view of the isthmus A colorized SEM of the ciliated lining of the uterine tube LM 122 a b c Regions of the uterine tubes, posterior view Hollow, muscular tubes about 13 cm long Transport oocyte from ovary to uterus 3 segments: infundibulum : expanded funnel near ovary > has fimbriae that extend into pelvic cavity ampulla : middle segment > smooth muscle layers in wall become thicker approaching uterus isthmus : short segment near uterus Uterine (Fallopian) Tubes Structure of Uterine Tube Mucosa : (folded) epithelium: > simple columnar ciliated > contains scattered mucin secreting cells lamina propria (CT) Muscularis externa : concentric smooth muscle layers around mucosa inner circular and outer longitudinal layers Serosa Uterine Tube & Oocyte Transport Few hours before ovulation, nerves from hypogastric plexus: turn on ciliary movement initiate peristaltic contractions in walls direction: > from infundibulum to uterine cavity Normally takes 34 days Uterine Tube & Fertilization For fertilization to occur: secondary oocyte must meet a sperm during first 1224 hours zygot Fertilization occurs in ampulla Unfertilized oocyte degenerates in terminal portions of uterine tubes or within uterus Uterine Tube & Nutrients Uterine tube provides nutrient-rich environment: > lipids and glycogen Nutrients supply spermatozoa and developing zygot Uterus Mesovarium Ovarian ligament Round ligament of uterus Perimetrium Myometrium Endometrium Uterine artery and vein Internal os of uterus Isthmus of uterus Cervical canal Vaginal artery External os of uterus Vaginal rugae Vagina Uterine cavity Body of uterus Ovary Broad ligament Fundus of uterus Uterine tube Ovarian artery and vein Suspensory ligament of ovary Cervix Anatomy of the Uterus Pear-shaped: 7.5L X 5W cm weight: 3040 g Has 3 regions: fundus, body (corpus), and cervix Normally bends anteriorly near base (anteflexion = anteversion ) Function: provides protection and nutrition and removes waste for embryo then fetus > Uterine > cavity > Body of > uterus > Fundus > of uterus > Cervix Uterine Support Pelvic floor Broad ligament Suspensory ligaments: round ligaments lateral (cardinal ) ligaments uterosacral ligaments Cervix of Uterus Inferior portion of uterus Extends from body into vagina Cervical canal : between 2 orifices: > internal os > external os Blood Supply of the Uterus Uterine arteries : arising from internal iliac arteries Ovarian arteries : arising from abdominal aorta Venous drainage : complementary to the arteries Nerve Supply of the Uterus Autonomic motor supply: sympathetic : hypogastric plexus parasympathetic : sacral segments S 3-S 4 Sensory supply: T11 -T 12 Segmental blocks : anesthetic procedure used during labor Uterine Wall Endometrium : = mucosa innermost layer thin, glandular, and highly vascular Myometrium : = muscularis externa thick, muscular layer Perimetrium : = serosa outermost layer incomplete serous membrane continuous with peritoneum covers fundus and posterior surface of body Vagina > Uterine > cavity Perimetrium > Myometrium > Endometrium Myometrium Thickest portion of the uterine wall 90% of the mass of the uterus 3 smooth muscle cell layers: > inner circular ,middle figure 8 , > and outer longitudinal Provides force to move fetus out of uterus into vagina Endometrium 2 zones undergo cyclical changes: basilar zone : deep > thinner layer > adjacent to myometrium > remains relatively constant functional zone : superficial > thicker layer > closer to uterine cavity > responds to sex hormones to produce characteristic features of uterine cycle Blood Supply of Endometrium Arcuate arteries : encircle endometrium Radial arteries : supply straight arteries (to basilar zone) supply spiral arteries (to functional zone) Uterine (Menstrual) Cycle Repeating series of endometrial changes Lasts from 21 to 35 days (average 28) 3 phases: menses (menstruation ) proliferative phase secretory phase Menses (Menstruation) Degeneration of functional zone: > lasts 17 days > sheds 3550 ml blood Caused by constriction of spiral arteries : > reducing blood flow, oxygen, and nutrients Weakened arterial walls rupture Degenerating tissues break away Entire functional zone is lost Basilar zone is not affected (supplied by straight arteries )Proliferative Phase Epithelial cells of uterine glands: multiply and spread across endometrial surface restore integrity of uterine epithelium Further growth and vascularization: completely restores functional zone Secretory Phase Generally lasts 14 days Endometrial glands enlarge: increase secretion Arteries of uterine wall: elongate spiral through functional zone Phases & Events of Ovarian & Uterine Cycles Uterine Cycle responds to hormones of ovarian cycle Menses and proliferative phase: occur during follicular phase of ovarian cycle Secretory phase: occurs during luteal phase phase of ovarian cycle: > begins at ovulation > persists as long as corpus luteum is intact Ovarian/Menstrual Cycle Menarche & Menopause Menarche : first uterine cycle begins at puberty (age 1112) Menopause : termination of uterine cycles age 4555 Abnormal Uterine Bleeding Menorrhagia : heavy , prolonged menstrual period at regular intervals Metrorrhagia : irregular uterine bleeding not related to menses Oligomenorrhea : infrequent menstruation episodes with intervals of more than 35 days Hypomenorrhea : scanty menstruation that lasts less than 2 days Amenorrhea Absence of menstruation Types: primary amenorrhea : > failure to initiate menses secondary amenorrhea : > interruption of 6 months or more > most common cause is Vagina Elastic, muscular tube Extends between cervix and vestibule 7.59 cm long Highly distensible Lies parallel to: rectum, posteriorly urethra, anteriorly Moistened by secretions of cervical glands Fornix : shallow recess surrounding cervical protrusion Histology of the Vagina Mucosa : epithelium : stratified squamous nonkeratinized forms folds (rugae) lamina propria : CT Muscularis : inner circular layer outer longitudinal layer Adventitia : dense fibrous CT smooth muscle cells Hymen Elastic epithelial fold: partially blocks entrance to vagina ruptures by trauma > e.g., sexual intercourse tampon usage > SEPTATE Blood & Nerve Supply of the Vagina Blood supply : vaginal branches of internal iliac (or uterine) arteries Nerve supply : hypogastric plexus (sympathetic) sacral nerves (parasympathetic) pudendal nerve (sensory) Functions of the Vagina Passageway for elimination of menstrual fluids Receives spermatozoa during sexual intercourse Forms inferior portion of birth canal Vaginal Bacteria A population of harmless resident bacteria ( Lactobacilli ): supported by nutrients in cervical mucus creates acidic environment restricts growth of many pathogens Vaginitis Inflammation of the vagina Causes infections : fungi, bacteria, or parasites low estrogen : atrophic vaginitis irritants : spermicides, perfumes, douches foreign bodies : tampons, condoms > Candida vaginitis Female Reproductive System Gonads: ovaries Ducts: uterine tubes, uterus, vagina Accessory glands : release secretions into female reproductive tract mammary glands External genitalia: vulva Uterine Glands Open onto endometrial surface Extend deep into lamina propria Manufacture mucus rich in glycogen: essential for survival of fertilized ovum Mammary Glands Accessory structure of integumentary system Tubuloalveolar glands Lie in pectoral fat pads deep to skin of chest Consist of lobes: 15-20/breast separated by dense connective tissue each contains several secretory lobules Mammary Gland Ducts Arise from lobules converge Lactiferous ducts : 1 per lobe form expanded chambers ( lactiferous sinuses ) open in nipples Areola : reddish-brown skin around each nipple Active Mammary Glands Do not complete development unless pregnancy occurs Secrete milk to nourish the infant ( lactation ) Controlled by: hormones: prolactine & sex hormone placenta Secretory alveoli Lactiferous duct Connective tissue Secretory alveoli Lactiferous duct Milk LM 100 An inactive mammary gland of a nonpregnant woman Resting mammary gland LM 131 Active mammary gland An active mammary gland of a nursing woman Female Reproductive System Gonads: ovaries Ducts: uterine tubes, uterus, vagina Accessory glands: release secretions into female reproductive tract mammary glands External genitalia : vulva Female External Genitalia (Vulva) Mons pubis and labia majora : outer limits of vulva contain sebaceous and apocrine sweat glands Labia minora : thin folds around the vestibule Vestibule : central space has openings of urethra and vagina Clitoris : small erectile protuberance in vestibule equivalent to the penis Glands of the Vestibule Paraurethral (Skenes ) glands : discharge into urethra near external opening Bartholins glands : secrete into vestibule near vaginal entrance Hormonal Regulation of the Female Reproductive Cycle > Involves secretions of hypothalamus , anterior pituitary and gonads > Forms a complex pattern that coordinates ovarian and uterine cycles Functions of Estrogen Maintains function of reproductive organs Maintains female secondary sex characters: > hair distribution, voice, fat distribution, Affects CNS activity (especially in hypothalamus, where estrogens increase the sexual drive) Initiates repair and growth of endometrium Stimulates bone and muscle growth Body Temperature & Ovulation Just before ovulation : estrogen dominates basal body temperature declines by 1 C Day after ovulation : progesterone dominates temperature rises by 1 CBody Temperature & Ovulation Just before ovulation : estrogen dominates basal body temperature declines by 1 C Day after ovulation : progesterone dominates temperature rises by 1 CCoitus (Copulation) Sexual intercourse: introduces semen into female reproductive tract Coordinated by sympathetic and parasympathetic divisions of ANS Sperms find their way for Impotence (ED) Male sexual dysfunction: an inability to achieve or maintain an erection caused by: > psychological factors > physical factors Sexually Transmitted Diseases (STDs) aka sexually transmitted infections (STI) Infections transferred by sexual intercourse Examples: bacterial : > gonorrhea, syphilis, chancroid, pelvic inflammatory disease (PID) viral : > herpes, genital warts, AIDS fungal : > candidiasis protozoal : > trichomoniasis Aging & the Reproductive System Male reproductive system: changes associated with andropause occur gradually, over longer time period Female reproductive system: changes associated with menopause Menopause Time that ovulation and menstruation cease Typically occurs around age 4555 Hormonal changes: levels of estrogens and progesterone levels of GnRH, FSH, and LH Premature menopause : depletion of ovarian follicles before age 40 Effect of Decreased Estrogen Levels Reduction in uterus and breast size Thinning of urethral and vaginal epithelia Osteoporosis Relationships between Reproductive & Other Systems Development

Title: Microsoft PowerPoint - Lecture 24 Reproductive Covid-19

URL Source: blob://pdf/87cd36a9-b68a-43a9-9b25-f4b7cb6aafbe

Markdown Content:
Anatomy of Reproductive System

Gonads :

organs that produce gametes and hormones

gametes : sperms & ova

Ducts :

receive and transport gametes

Accessory glands :

secrete fluids into ducts

External genitalia :

perineal structures Types of Reproductive System

## Male reproductive system

## Female reproductive system Male Reproductive System

Major Structures

of the Male

Reproductive System

Ducts

Gonad

External Genitalia

Prostatic urethra

Pubic symphysis

Ejaculatory duct

Membranous urethra

Spongy urethra

Ductus deferens

Epididymis

Testis

Penis

Scrotum

Urinary bladder

Ureter

Seminal gland

Rectum

Prostate gland

External urethral orifice

Anus

Accessory Glands

Corpus spongiosum

Corpus cavernosum

Bulbourethral gland Anatomy of Male Reproductive System

Gonads :

testes

Ducts :

epididymis, vas (ductus) deferens, ejaculatory duct, urethra

Accessory glands :

seminal vesicles, prostate, bulbourethral glands

External genitalia :

scrotum, penis Anterior View of Male Reproductive System:

Spermatic Cord

Urinary

bladder

Spermatic Cord

Inguinal

canal

Ductus deferens

Genitofemoral nerve

Deferential artery

Pampiniform plexus

Testicular artery

Epididymis

Scrotal cavity

Testis (covered by visceral

layer of tunica vaginalis)

Parietal layer of

tunica vaginalis

(inner lining of cremaster,

facing scrotal cavity)

Raphe

Testicular artery

Testicular vein

Penis

Inguinal ligament

Superficial

inguinal ring

Spermatic cord

Scrotal septum

Cremaster muscle with

cremasteric fascia

Superficial scrotal

fascia

Dartos muscle

Scrotal skin (cut)

Layers of the Scrotum Spermatic Cord

Fibromuscular tube:

consists of layers of fascia and smooth muscle

Extends between abdominopelvic cavity

and testis

Encloses:

vas deferens

testicular vessels, lymphatics, and nerves

Passes through inguinal canal

> Spermatic Cord
> Inguinal
> canal
> Ductus deferens
> Genitofemoral nerve
> Deferential artery
> Pampiniform plexus
> Testicular artery

Inguinal Canals

Passageways through abdominal musculature

Form during development as testes descend into scrotum Inguinal Hernia

Protrusion of visceral tissues into inguinal canal through a

defect in the wall

Types: Male Reproductive System

Gonads :

testes

Ducts:

epididymis, vas (ductus) deferens, ejaculatory duct, urethra

Accessory glands:

seminal vesicles, prostate, bulbourethral glands

External genitalia:

scrotum, penis Testes

Egg-shaped (5L X 3W X 2.5T cm)

Weight: 1015 g

Hang in scrotum :

normal sperm development in testes requires

temperatures 1C < body temperature

Function:

produce male gametes ( spermatozoa = sperms):

> 1/2 billion sperms / day

secrete male sex hormones ( androgens )Formation & Descent of the Testes

Testes form inside the abdominal

cavity adjacent to kidneys

Descend through abdominal cavity

Reach the scrotum at birth

> Peritoneum
> Gubernaculum
> testis
> Testis
> Colon
> 2 months
> 5 mm
> Umbilical
> cord
> Penis
> 3 months
> 5 mm
> 5 mm
> Birth
> Scrotum
> Testis
> Pubis
> Testis

Structure of the Testes

Ductus deferens

Epididymis

Efferent ductule

Skin

Scrotum

Dartos muscle

Superficial

scrotal fascia

Cremaster muscle

Tunica vaginalis

Tunica albuginea

Scrotal cavity

Septa

Lobule Raphe

Septa

Seminiferous

tubules

Straight

tubule

Rete

testis

Mediastinum of testis

Testis

A section through a testis

LM  26 Covering of the Testis

Scrotum :

skin:

dartos muscle: smooth muscle in dermis

superficial fascia (subcutaneous tissue)

Cremaster muscle :

skeletal muscle layer deep to the scrotum

Tunica vaginalis :

serous membrane lines scrotal cavity

visceral & parietal layers with a cavity

Tunica albuginea

> Ductus deferens
> Epididymis
> Efferent ductule
> Skin

Scrotum

> Dartos muscle
> Superficial
> scrotal fascia
> Cremaster muscle
> Tunica vaginalis
> Tunica albuginea
> Scrotal cavity
> Septa
> Lobule

6Tunica Albuginea

Dense connective tissue layer covers the

testis

Continuous with fibers surrounding

epididymis

Extends into substance of testis

form fibrous partitions ( septa )

divide testis into lobules

> Ductus deferens
> Epididymis
> Efferent ductule
> Skin

Scrotum

> Dartos muscle
> Superficial
> scrotal fascia
> Cremaster muscle
> Tunica vaginalis
> Tunica albuginea
> Scrotal cavity
> Septa
> Lobule

Testicular Lobules

Each testis contains 250-400 lobules

Each lobule contains 1-3 slender tightly-

coiled seminiferous tubules

Ductus deferens

Epididymis

Efferent ductule

Skin

Scrotum

Dartos muscle

Superficial

scrotal fascia

Cremaster muscle

Tunica vaginalis

Tunica albuginea

Scrotal cavity

Septa

Lobule Seminiferous Tubules

Sperm factory

Testis contains about 1/2 mile of tightly-coiled seminiferous

tubules

Each seminiferous tubule:

80 cm long

forms a loop connected to rete testis :

a network of passageways

> Seminiferous
> tubules
> Straight
> tubule
> Rete
> testis

## Seminiferous Tubules Interstitial Cells (of Leydig)

Located in connective tissue capsules surround seminiferous

tubules

Produce androgens :

> e.g., testosterone

Sustentacular (Sertoli, Nurse) Cells

Extend from tubular capsule to lumen of seminiferous tubules

Function:

support spermatogenesis :

under effect of FSH and testosterone

secretory function :

e.g., inhibin hormone and androgen binding protein

maintain bloodtestis barrier :

isolates seminiferous tubules through tight junctions Spermatogenesis

Process of sperms production

Begins at puberty

In seminiferous tubules:

begins at outermost cell layer

proceeds toward lumen

3 integrated processes:

mitosis

meiosis

spermiogenesis

Spermatogenesis

Mitosis of spermatogonium

Meiosis I

Meiosis II

Spermiogenesis

(physical maturation)

Primary

spermatocyte

(diploid, 2n)

DNA replication

Primary

spermatocyte

Synapsis and

tetrad formation

Secondary

spermatocytes

Spermatids

(haploid, n)

Spermatozoa

(haploid, n)

23 Steps of Spermatogenesis

Mitosis:

spermatogonia (stem cells)  2 daughter cells:

1 remains as spermatogonium

second differentiates into primary spermatocyte  DNA replication

Meosis:

Meosis I : primary spermatocytes  secondary spermatocytes

Meosis II : secondary spermatocytes  spermatids

Spermiogenesis:

spermatids (immature)  spermatozoa (mature):

lose contact with wall of seminiferous tubule

enter lumen (= spermiation)  Meiosis produces gametes that contain 1/2 of chromosomes in

somatic cells

For each cell entering meiosis:

testes produce 4 spermatozoa

ovaries produce 1 ovum and 3 polar bodies

Cells & Meiosis Structure of a Spermatozoon

Head :

contains nucleus and chromosomes

has an acrosomal cap at tip:

contains enzymes for fertilization

Neck :

contains centrioles

Middle piece :

contains mitochondria

Tail (flagellum ):

whip-like organelle to move the sperm Sperm Maturation

Testes produce sperms that are:

physically mature

functionally immature

Other parts of reproductive system are responsible for:

functional maturation, nourishment, storage, and transport Male Reproductive System

Gonads:

testes

Ducts :

epididymis, vas (ductus) deferens, ejaculatory duct, urethra

Accessory glands:

seminal vesicles, prostate, bulbourethral glands

External genitalia:

scrotum, penis  Epididymis

Vas (ductus ) deferens

Ejaculatory duct

Urethra

Ducts

Prostatic urethra

Pubic symphysis

Ejaculatory duct

Membranous urethra

Spongy urethra

Ductus deferens

Epididymis

Testis

Penis

Scrotum

Urinary bladder

External urethral orifice

Corpus spongiosum

Corpus cavernosum

Ducts (Passageways of Spermatozoa) Efferent Ductules

1520 large efferent ductules :

connect rete testis to epididymis

> Ductus deferens
> Epididymis
> Efferent ductule
> Straight
> tubule
> Rete
> testis

Epididymis

Start of passageways of sperms

Coiled tube almost 7 m long:

bound to posterior border of testis

Parts:

head :

proximal to the testis

body :

at posterior margin of testis

tail :

near inferior border of testis

primary storage location of sperms Functions of the Epididymis

Functional maturation of spermatozoa

Stores spermatozoa

Recycles damaged spermatozoa

Monitors and adjusts fluid produced by seminiferous tubules Vas (Ductus) Deferens

Ureter

Ductus deferens

Seminal gland

Ampulla of

ductus deferens

Duct of

seminal gland

Ejaculatory duct

Prostate gland

Prostatic urethra

A posterior view of the urinary

bladder and prostate gland,

showing subdivisions of the

ductus deferens in relation

to surrounding structures.

Connective

tissue and

smooth

muscle

Prostatic

(tubuloalveolar)

glands

Histological detail of the glands of the prostate. The tissue

between the individual glandular units consists largely of

smooth muscle. Contractions of this muscle tissue help

move the secretions into the ejaculatory duct and urethra.

Histology of the bulbourethral glands, which

secrete a thick mucus into the spongy urethra.

Histology of the seminal glands. These organs

produce most of the volume of seminal fluid.

Light micrograph showing the

thick layers of smooth muscle in

the wall of the ductus deferens.

Lumen

of ductus

deferens

Smooth

muscle

Lumen

Secretory

pockets

Smooth

muscle

Bulbourethral glands

Urogenital diaphragm

Smooth

muscle

Capsule

Mucous

glands

Ductus

deferens

LM  120

Seminal gland LM  45

Bulbourethral gland LM  175 Prostate gland LM 50

Urinary

bladder

Lumen Vas Deferens

3045 cm long cord

Begins at tail of the epididymis

Ascends through inguinal canal:

> within the spermatic cord

Curves inferiorly along urinary bladder

Lumen enlarges at the end into ampulla

Opens in the ejaculatory duct

Can store sperms for several months Structure of Vas Deferens

Lined by pseudostratified columnar ciliated

epithelium

Wall contains thick smooth muscle layer :

inner & outer longitudinal

middle circular

peristaltic contractions propel spermatozoa

and fluid

> Lumen of ductus
> deferens
> Smooth
> muscle

Stereocilia = non motile cilia Vasectomy

Surgical cut of the 2 vasa deferentia

Effective method of contraception

Comparable to tubal ligation in females Ejaculatory Duct

Short passageway (2 cm) at junction of ampulla and seminal

vesicle duct

Penetrates wall of prostate gland

Empties into urethra Male Urethra

1820 cm long

Extends from bladder neck to

tip of penis

Divided into 3 parts:

prostatic urethra :

passes through center of prostate gland

membranous urethra :

short segment that penetrates the urogenital diaphragm

spongy (penile ) urethra :

from urogenital diaphragm to external urethral orifice

> Prostatic urethra
> Ejaculatory duct
> Membranous urethra
> Spongy urethra
> Ductus deferens
> Epididymis
> Testis
> Penis
> Urinary bladder
> Ureter
> Rectum

Male Reproductive System

Gonads:

testes

Ducts:

epididymis, vas (ductus) deferens, ejaculatory duct, urethra

Accessory glands :

seminal vesicles, prostate, bulbourethral glands

External genitalia:

scrotum, penis Accessory Glands

Seminal vesicles

Prostate

Bulbourethral glands

Secrete fluids into ejaculatory ducts & urethra

Seminal gland

Duct of

seminal gland

Ejaculatory duct

Prostate gland

Prostatic urethra

Bulbourethral glands

Urogenital diaphragm

> Urinary
> bladder

Seminal Fluid

Mixture of secretions from accessory glands:

each with distinctive biochemical characteristics

contains enzymes: e.g., protease, fibrinolysin

Function:

activates spermatozoa

provides nutrients for spermatozoa

produces buffers to counteract acidity of urethra and vagina

facilitates movement of spermatozoa Seminal Vesicles

2 tubular glands:

coiled and folded

5 X 2.5 cm

Produce about 60% of

seminal fluid

> Lumen
> Secretory
> pockets
> Smooth
> muscle

Vesicular Fluid

Composition:

fructose : for nutrition

prostaglandins : stimulate smooth muscle contractions (male and

female)

fibrinogen : forms temporary clot in vagina

Slightly alkaline

Has same osmotic concentration as plasma

Discharged into ejaculatory duct  Compound tubuloalveolar gland

Surrounded by smooth muscle

fibers

4 cm in diameter

Encircles proximal portion of

urethra:

below urinary bladder

Produces 20-30% of seminal

fluid

Prostate Connective tissue and smooth muscle

> Prostatic glands

Prostatic Fluid

Slightly acidic

Contains antibiotic seminalplasmin

Ejected into prostatic urethra Bulbourethral (Cowpers) Glands

2 compound tubuloalveolar

mucous glands

Round shaped

1 cm in diameter

Located at base of penis

Empty into urethral lumen

> Smooth
> muscle
> Capsule
> Mucous
> glands
> Lumen

Bulbourethral Secretion

Thick mucus

Alkaline

Function:

Neutralizes acids in urethra and vagina

lubricates the glans Semen

Semen = spermatozoa + seminal fluid

Volume (= ejaculate ):

typical ejaculation releases 25 ml

low volume may indicate problems with prostate or seminal vesicles Sperm Count

Normal range: 20100 million spermatozoa/ml of ejaculate

> SEM 780

Semen Analysis

Volume

Sperm count

Morphology

Motility

Male Reproductive System

Gonads:

testes

Ducts:

epididymis, vas (ductus) deferens, ejaculatory duct, urethra

Accessory glands:

seminal vesicles, prostate, bulbourethral glands

External genitalia :

scrotum, penis External Genitalia

Scrotum :

fleshy pouch

encloses testes

Penis :

erectile organ

contains distal portion of urethra Scrotum

Divided into 2 chambers ( scrotal cavities )

Each testis lies in a separate chamber

Structure:

skin:

dartos muscle : in the dermis

superficial fascia (subcutaneous tissue)

> Skin
> Scrotum
> Dartos muscle
> Superficial
> scrotal fascia

Penis

Tubular organ:

through which distal portion of urethra

passes

Function:

conducts urine to exterior

introduces semen into female vagina Regions of the Penis

Root :

fixed portion of penis

attaches penis to body wall

Shaft :

movable portion of the penis

contains erectile tissue

Neck :

narrow portion between shaft and glans

Glans :

expanded distal end of penis:

surrounds external urethral orifice Prepuce (Foreskin)

Fold of skin surrounding tip of penis

Attaches to neck and continues over glans

Preputial glands :

small glands at the base of the glans

secrete smegma :

> waxy material
> support bacterial growth

Circumcision

Surgical removal of the prepuce Erectile Tissue

In shaft of penis

Contains network of vascular channels:

incompletely separated by partitions of elastic connective tissue and

smooth muscle fibers

3 cylindrical columns:

2 corpora cavernosa

1 corpus spongiosum Corpora Cavernosa

2 cylindrical masses of erectile tissue:

under anterior surface of flaccid penis

encircled by dense collagenous sheath

each surrounds a central artery

Diverge at their bases:

forming crura of penis:

each crus is bound to ramus of ischium and pubis:

> by tough connective-tissue ligaments
> Right crus
> of penis

Corpus Spongiosum

Surrounds penile urethra

Relatively slender

Expands to form the glans

Surrounded by a sheath:

with more elastic fibers than corpora cavernosa

Erectile tissue contains a pair of small arteries Erectile Function

Resting state (flaccid penis):

arterial branches are constricted

muscular partitions are tense

blood flow into erectile tissue is restricted

Erection (penis stiffens):

arterial dilation

increased blood flow

assumes more upright position Male reproductive function is regulated by the

complex interaction of hormones from the hypothalamus,

anterior lobe of the pituitary gland, and the testes.

Negative feedback systems keep testosterone levels

within a relatively narrow range until late in life.

Release of Gonadotropin-

Releasing Hormone (GnRH)

The hypothalamus secretes

the hormone GnRH at a rate

that remains relatively steady.

As a result, blood levels of

FSH, LH, and testosterone

remain within a relatively

narrow range throughout a

mans reproductive life.

High testosterone levels

inhibit the release of GnRH

by the hypothalamus,

causing a decrease in

LH secretion, which

lowers testosterone to

normal levels.

Negative feedback

When stimulated by GnRH, the anterior

lobe of the pituitary gland releases

luteinizing hormone (LH) and follicle-

stimulating hormone (FSH).

Inhibin depresses the

pituitary production of

FSH, and perhaps the

hypothalamic secretion of

gonadotropin-releasing

hormone (GnRH).The

faster the rate of sperm

production, the more

inhibin is secreted. By

regulating FSH and GnRH

secretion, nurse cells

provide feedback control

of spermatogenesis.

Secretion of Follicle-

Stimulating Hormone

(FSH)

FSH targets primarily

the nurse cells of the

seminiferous tubules.

Secretion of

Luteinizing

Hormone (LH)

LH targets the

interstitial cells

of the testes.

Interstitial Cell Stimulation

LH induces the secretion of

testosterone and other androgens

by the interstitial cells of the testes.

Nurse Cell Stimulation

Under FSH stimulation, and with

testosterone from the interstitial cells,

nurse cells (1) secrete inhibin in

response to factors released by

developing spermatozoa, (2) secrete

androgen-binding protein (ABP), and

(3) promote spermatogenesis and

spermiogenesis.

> Negative feedback

Inhibin

Testosterone

Peripheral Effects of Testosterone Androgen-binding protein (ABP)

binds androgens within the

seminiferous tubules, which

increases the local concentration of

androgens and stimulates the

physical maturation of spermatids.

Nurse cell

environment

facilitates both

spermatogenesis

and

spermiogenesis.

Maintains libido

(sexual drive)

and related

behaviors

Stimulates

bone and

muscle

growth

Establishes and

maintains male

secondary sex

characteristics

Maintains accessory

glands and organs

of the male

reproductive system

KEY

Stimulation

Inhibition

HYPOTHALAMUS

LOBE OF THE

PITUITARY

GLAND

TESTES

Hormonal Regulation of Male Reproductive Function Functions of Testosterone

Stimulates spermatogenesis

Maintains male reproductive organs

Establishes male secondary sex characters :

hair distribution, deep voice, muscle mass, adipose tissue deposits,

Enhances libido and related behaviors

Stimulates metabolism : e.g.

protein synthesis - muscle and bone growth

blood cell formation Estradiol

Produced in small amounts by:

gonads :

70%: converted from circulating testosterone by aromatase enzyme

30%: secreted by interstitial and sustentacular cells of testes

adrenal cortex :

zona reticularis Rectouterine

pouch

Vesicouterine

pouch

Urinary bladder

Urethra

Pubic symphysis

Accessory Glands

Paraurethral

glands

Greater vestibular

gland

Clitoris

Ovarian

follicle

Sigmoid

colon

Rectum

Anus

Major Structures

of the Female

Reproductive System

Ovary

Uterine tube

Uterus

Vagina

External Genitalia

Perimetrium

Myometrium

Endometrium

Cervix

Labium minus

Labium majus

## Female Reproductive System Anatomy of Female Reproductive System

Gonads :

ovaries

Ducts :

uterine (Fallopian) tubes, uterus, vagina

Accessory glands :

release secretions into female reproductive tract

mammary glands

External genitalia :

vulva Function of Female Reproductive System

Produces sex hormones and functional gametes

Protects and supports developing embryo

Nourishes newborn infant Structural Support

Ovarian artery

and vein

Fimbriae Uterine tube

Suspensory

ligament

Infundibulum

Ovary

Ureter

Uterosacral ligament

External os

Cervix

Vaginal rugae

Vaginal wall

Uterus

Broad ligament

Ovarian

ligament

Mesovarium Suspensory

ligament

Retractor

Structures Stabilizing the Ovary

Broad ligament :

encloses ovaries,

uterine tubes, and

uterus Broad Ligament

Continuation of parietal peritoneum

Connects reproductive organs to the walls and floor of

the pelvis

Subdivides peritoneal cavity into:

rectouterine pouch :

> between uterus and rectum

vesicouterine pouch :

> between uterus and bladder

Broad Ligament

Continuation of parietal peritoneum

Connects reproductive organs to the walls and floor of

the pelvis

Subdivides peritoneal cavity into:

rectouterine pouch :

> between uterus and rectum

vesicouterine pouch :

> between uterus and bladder
> Vesicouterine
> pouch

Divisions of Broad Ligament

Mesometrium :

mesentery of the uterus

largest portion

Mesosalpinx :

surrounds each uterine tube

Mesovarium :

surrounds and stabilizes each ovary Female Reproductive System

Gonads :

ovaries

Ducts:

uterine tubes, uterus, vagina

Accessory glands:

release secretions into female reproductive tract

mammary glands

External genitalia:

vulva Ovaries

> Uterine
> tube
> Corpus
> luteum
> Cortex
> Tunica
> albuginea
> Mature
> follicle
> Germinal
> epithelium
> Egg
> nest
> Ovarian
> hilum
> Broad ligament
> Mesovarium
> Mesosalpinx
> Mesenteries of
> the Ovary and
> Uterine Tube

Almond-shaped organs

5L X 2.5W X 0.8T cm

Weight: 68 g

Near lateral walls of pelvic cavity

Function:

produce female gametes ( ova or oocytes)

secrete female sex hormones ( estrogens and progestins )Ovarian Support

Mesovarium

Ovarian ligament :

extends from uterus to ovary

Suspensory ligament :

extends from ovary to pelvic wall

contains ovarian artery and vein

> Uterus
> Broad ligament
> Ovarian
> ligament
> Mesovarium Suspensory
> ligament Retractor
> Structures Stabilizing the Ovary

Covering of The Ovary

Germinal epithelium : outer

layer of visceral peritoneum

consists of columnar epithelial cells

Tunica albuginea : inner

layer of connective tissue

> Cortex
> Tunica
> albuginea
> Mature
> follicle
> Germinal
> epithelium
> Egg
> nest
> Ovarian
> hilum
> Medulla

Structure of The Ovary

Superficial cortex :

contains:

ovarian follicles

stroma: CT

Deep medulla

contains blood vessels, lymphatics, and nerves

> Cortex
> Tunica
> albuginea
> Mature
> follicle
> Germinal
> epithelium
> Egg
> nest
> Ovarian
> hilum
> Medulla

Oogenesis

Process of ova production

Begins before birth

Accelerates at puberty

Ends at menopause

2 processes:

mitosis

meiosis

Oogenesis

Mitosis of oogonium

Meiosis I

Meiosis II

Oogonium

(stem cell)

Primary

oocyte

(diploid, 2n)

DNA replication

Primary

oocyte

Tetrad

First polar

body

Secondary

oocyte

First polar body

may not complete

meiosis II

Secondary oocyte

released (ovulation) in

metaphase of meiosis II

Second

polar

body

Nucleus

of oocyte

(n)

Sperm

(n)

Fertilization

(see Figure 291)

23 Process of Oogenesis: Female Fetal Development

Oogonia (stem cells ):

complete mitotic divisions before birth

Between third and seventh months of intrauterine life:

primary oocytes :

prepare for meiosis

stop at prophase of meiosis I

remain in suspended development till puberty Process of Oogenesis: Puberty

Rising FSH triggers start of ovarian cycle

Each month thereafter:

some primary oocytes are stimulated to develop  secondary

oocytes (stop in metaphase II until fertilization)

if fertilization occurs  meosis II is completed  ovum Steps of Oogenesis: Summary

Oogonium  (mitosis )  primary oocyte

Primary oocyte  (meiosis I )  first polar body [discarded] +

secondary oocyte

Secondary oocyte  (meiosis II )  second polar body

[discarded] + ovum  Meiosis produces gametes that contain 1/2 of chromosomes in

somatic cells

For each cell entering meiosis:

testes produce 4 spermatozoa

ovaries produce 1 ovum and 3 polar bodies

Cells & Meiosis Spermatogenesis

Mitosis of spermatogonium

Each division of a diploid spermatogonium produces two

daughter cells. One is a spermatogonium that remains in

contact with the basement membrane of the tubule, and

the other is a primary spermatocyte that is displaced

toward the lumen. These events from spermatogonium

to primary spermatocyte take 16 days.

Meiosis I

Meiosis II

Spermiogenesis (physical maturation)

As meiosis I begins, each primary spermatocyte

contains 46 individual chromosomes. At the end

of meiosis I, the daughter cells are called secondary

spermatocytes. Every secondary spermatocyte

contains 23 chromosomes, each with a pair of

duplicate chromatids. This phase of spermatogenesis

takes about 24 days.

The secondary spermatocytes soon enter

meiosis II, which yields four haploid

spermatids , each containing 23

chromosomes. For each primary spermatocyte

that enters meiosis, four spermatids are

produced. This phase lasts only a few hours.

In spermiogenesis, the last step of

spermatogenesis, each spermatid matures

into a single spermatozoon, or sperm. The

process of spermiogenesisfrom

spermatids to spermatozoatakes 24 days.

Primary

spermatocyte

(diploid, 2n)

DNA replication

Primary

spermatocyte

Synapsis and

tetrad formation

Secondary

spermatocytes

Spermatids

(haploid, n)

Spermatozoa

(haploid, n)

Oogenesis

Mitosis of oogonium

Unlike spermatogonia, the oogonia

(--G-n-uh), or female reproductive

stem cells, complete their mitotic

divisions before birth.

Meiosis I

Between the third and seventh months of fetal

development, the daughter cells, or primary

oocytes (--sts), prepare to undergo

meiosis. They proceed as far as the prophase of

meiosis I, but then the process comes to a halt.

The primary oocytes remain in a state of

suspended development until puberty,

when rising levels of FSH trigger the

start of the ovarian cycle. Each month

after the ovarian cycle begins, some of

the primary oocytes are stimulated to

undergo further development. Meiosis I

is then completed, yielding a secondary

oocyte and a polar body.

Meiosis II

Each month after the ovarian

cycle begins, one or more

secondary oocytes leave the

ovary suspended in metaphase

of meiosis II.

At the time of fertilization, a

second polar body forms and

the fertilized oocyte is then

called a mature ovum. (A cell

in any of the preceding steps in

oogenesis is sometimes called

an immature ovum.)

Oogonium

(stem cell)

Primary

oocyte

(diploid, 2n)

DNA replication

Primary

oocyte

Tetrad

First polar

body

Secondary

oocyte

First polar body

may not complete

meiosis II

Secondary oocyte

released (ovulation) in

metaphase of meiosis II

Second

polar

body

Nucleus

of oocyte

(n)

Sperm

(n)

Fertilization Ovarian Follicle

Basic unit of female reproductive biology

Located in cortex of ovaries

Passes through different phases of maturation

Composition depends on degree of maturation Structure of Mature (Graafian) Follicle

Secondary

oocyte

Antrum

Granulosa

cells

Corona

radiata

LM 136 Structure of Mature (Graafian) Follicle

1. Secondary oocyte

2. Granulosa cells

3. Corona radiata:

granulosa cells surround oocyte

4. Zona pellucida:

glycoprotein layer around oocyte

5. Theca cells:

interna and externa

secrete androgen and estrogen

6. Antrum:

contains follicular fluid

> 1
> 6
> 2
> 3
> 5
> 4

Ovarian Follicle Atresia

Degeneration of primordial follicles

Ovaries have about 2 million primordial follicles at birth:

each contains a primary oocyte

By puberty:

number drops to about 400,000 Ovarian Cycle

Monthly oogenesis :

between puberty and menopause

After sexual maturation:

a different group of primordial follicles is activated each month

Divided into:

follicular phase (preovulatory phase)

luteal phase (postovulatory phase) Steps of Ovarian Cycle Corpus Luteum

Ovarian follicle after ovulation

Produces progestins (progesterone ):

prepares uterus for pregnancy

If fertilization does not occur :

degenerates about 12 days after ovulation

fills with scar tissue to become corpus albicans

> Corpus luteum Corpus albicans

Female Reproductive System

Gonads:

ovaries

Ducts :

uterine tubes, uterus, vagina

Accessory glands:

release secretions into female reproductive tract

mammary glands

External genitalia:

vulva Uterine (Fallopian) Tubes Ampulla Isthmus

Fimbriae

Uterus

Infundibulum

Microvilli

of mucin-

secreting

cells

Cilia

Epithelial surface SEM 4000 Isthmus

Smooth

muscle

Lamina

propria

Columnar

epithelium

A sectional view of

the isthmus

A colorized SEM of the ciliated

lining of the uterine tube

LM 122

b c

Regions of the uterine

tubes, posterior view  Hollow, muscular tubes about 13 cm long

Transport oocyte from ovary to uterus

3 segments:

infundibulum : expanded funnel near ovary

has fimbriae that extend into pelvic cavity

ampulla : middle segment

smooth muscle layers in wall become

thicker approaching uterus

isthmus : short segment near uterus

Uterine (Fallopian) Tubes Structure of Uterine Tube

Mucosa : (folded)

epithelium:

simple columnar ciliated

contains scattered mucin secreting cells

lamina propria (CT)

Muscularis externa :

concentric smooth muscle layers around mucosa

inner circular and outer longitudinal layers

Serosa Uterine Tube & Oocyte Transport

Few hours before ovulation, nerves from hypogastric plexus:

turn on ciliary movement

initiate peristaltic contractions in walls

direction:

> from infundibulum to uterine cavity

Normally takes 34 days Uterine Tube & Fertilization

For fertilization to occur:

secondary oocyte must meet a sperm during first 1224 hours

zygot

Fertilization occurs in ampulla

Unfertilized oocyte degenerates in terminal portions of uterine

tubes or within uterus Uterine Tube & Nutrients

Uterine tube provides nutrient-rich environment:

> lipids and glycogen

Nutrients supply spermatozoa and developing zygot Uterus

Mesovarium

Ovarian ligament

Round ligament

of uterus

Perimetrium

Myometrium

Endometrium

Uterine artery

and vein

Internal os of uterus

Isthmus of uterus

Cervical canal

Vaginal artery

External os

of uterus

Vaginal rugae

Vagina

Uterine

cavity

Body of

uterus Ovary

Broad ligament

Fundus

of uterus

Uterine tube

Ovarian artery

and vein

Suspensory

ligament of ovary

Cervix Anatomy of the Uterus

Pear-shaped:

7.5L X 5W cm

weight: 3040 g

Has 3 regions:

fundus, body (corpus), and cervix

Normally bends anteriorly near base

(anteflexion = anteversion )

Function:

provides protection and nutrition and removes waste

for embryo then fetus

> Uterine
> cavity
> Body of
> uterus
> Fundus
> of uterus
> Cervix

Uterine Support

Pelvic floor

Broad ligament

Suspensory ligaments:

round ligaments

lateral (cardinal ) ligaments

uterosacral ligaments Cervix of Uterus

Inferior portion of uterus

Extends from body into vagina

Cervical canal :

between 2 orifices:

> internal os
> external os

Blood Supply of the Uterus

Uterine arteries :

arising from internal iliac arteries

Ovarian arteries :

arising from abdominal aorta

Venous drainage :

complementary to the arteries Nerve Supply of the Uterus

Autonomic motor supply:

sympathetic : hypogastric plexus

parasympathetic : sacral segments S 3-S 4

Sensory supply:

T11 -T 12

Segmental blocks :

anesthetic procedure used during labor Uterine Wall

Endometrium : = mucosa

innermost layer

thin, glandular, and highly vascular

Myometrium : = muscularis externa

thick, muscular layer

Perimetrium : = serosa

outermost layer

incomplete serous membrane continuous with peritoneum

covers fundus and posterior surface of body Vagina

> Uterine
> cavity Perimetrium
> Myometrium
> Endometrium

Myometrium

Thickest portion of the uterine wall

90% of the mass of the uterus

3 smooth muscle cell layers:

> inner circular ,middle figure 8 ,
> and outer longitudinal

Provides force to move fetus out of

uterus into vagina Endometrium

2 zones undergo cyclical changes:

basilar zone : deep

thinner layer

adjacent to myometrium

remains relatively constant

functional zone : superficial

thicker layer

closer to uterine cavity

responds to sex hormones to produce characteristic features of uterine cycle Blood Supply of Endometrium

Arcuate arteries :

encircle endometrium

Radial arteries :

supply straight arteries (to basilar zone)

supply spiral arteries (to functional zone) Uterine (Menstrual) Cycle

Repeating series of endometrial changes

Lasts from 21 to 35 days (average 28)

3 phases:

menses (menstruation )

proliferative phase

secretory phase Menses (Menstruation)

Degeneration of functional zone:

> lasts 17 days 
> sheds 3550 ml blood

Caused by constriction of spiral arteries :

> reducing blood flow, oxygen, and nutrients

Weakened arterial walls rupture

Degenerating tissues break away

Entire functional zone is lost

Basilar zone is not affected (supplied by straight arteries )Proliferative Phase

Epithelial cells of uterine glands:

multiply and spread across endometrial surface

restore integrity of uterine epithelium

Further growth and vascularization:

completely restores functional zone Secretory Phase

Generally lasts 14 days

Endometrial glands enlarge:

increase secretion

Arteries of uterine wall:

elongate

spiral through functional zone Phases & Events of Ovarian & Uterine Cycles

Uterine Cycle responds to hormones of ovarian cycle

Menses and proliferative phase:

occur during follicular phase of ovarian cycle

Secretory phase:

occurs during luteal phase phase of ovarian cycle:

> begins at ovulation
> persists as long as corpus luteum is intact

Ovarian/Menstrual Cycle Menarche & Menopause

Menarche :

first uterine cycle

begins at puberty (age 1112)

Menopause :

termination of uterine cycles

age 4555 Abnormal Uterine Bleeding

Menorrhagia :

heavy , prolonged menstrual period at regular intervals

Metrorrhagia :

irregular uterine bleeding not related to menses

Oligomenorrhea :

infrequent menstruation episodes with intervals of more than 35 days

Hypomenorrhea :

scanty menstruation that lasts less than 2 days Amenorrhea

Absence of menstruation

Types:

primary amenorrhea :

failure to initiate menses

secondary amenorrhea :

interruption of 6 months or more

most common cause is  Vagina

Elastic, muscular tube

Extends between cervix and vestibule

7.59 cm long

Highly distensible

Lies parallel to:

rectum, posteriorly

urethra, anteriorly

Moistened by secretions of cervical glands

Fornix :

shallow recess surrounding cervical protrusion Histology of the Vagina

Mucosa :

epithelium : stratified squamous nonkeratinized

forms folds (rugae)

lamina propria : CT

Muscularis :

inner circular layer

outer longitudinal layer

Adventitia :

dense fibrous CT

smooth muscle cells Hymen

Elastic epithelial fold:

partially blocks entrance to vagina

ruptures by trauma

e.g., sexual intercourse  tampon usage

> SEPTATE

Blood & Nerve Supply of the Vagina

Blood supply :

vaginal branches of internal iliac (or uterine) arteries

Nerve supply :

hypogastric plexus (sympathetic)

sacral nerves (parasympathetic)

pudendal nerve (sensory) Functions of the Vagina

Passageway for elimination of menstrual fluids

Receives spermatozoa during sexual intercourse

Forms inferior portion of birth canal Vaginal Bacteria

A population of harmless resident bacteria ( Lactobacilli ):

supported by nutrients in cervical mucus

creates acidic environment

restricts growth of many pathogens Vaginitis

Inflammation of the vagina

Causes

infections : fungi, bacteria, or parasites

low estrogen : atrophic vaginitis

irritants : spermicides, perfumes, douches

foreign bodies : tampons, condoms

> Candida vaginitis

Female Reproductive System

Gonads:

ovaries

Ducts:

uterine tubes, uterus, vagina

Accessory glands :

release secretions into female reproductive tract

mammary glands

External genitalia:

vulva Uterine Glands

Open onto endometrial surface

Extend deep into lamina propria

Manufacture mucus rich in glycogen:

essential for survival of fertilized ovum Mammary Glands

Accessory structure of integumentary system

Tubuloalveolar glands

Lie in pectoral fat pads deep to skin of chest

Consist of lobes:

15-20/breast

separated by dense connective tissue

each contains several secretory lobules Mammary Gland Ducts

Arise from lobules  converge

Lactiferous ducts :

1 per lobe

form expanded chambers ( lactiferous sinuses )

open in nipples

Areola :

reddish-brown skin around each nipple Active Mammary Glands

Do not complete development unless pregnancy

occurs

Secrete milk to nourish the infant ( lactation )

Controlled by:

hormones:

prolactine & sex hormone

placenta

Secretory alveoli

Lactiferous duct

Connective

tissue

Secretory alveoli

Lactiferous duct

Milk

LM  100

An inactive mammary gland

of a nonpregnant woman

Resting mammary gland

LM  131 Active mammary gland

An active mammary gland of a

nursing woman Female Reproductive System

Gonads:

ovaries

Ducts:

uterine tubes, uterus, vagina

Accessory glands:

release secretions into female reproductive tract

mammary glands

External genitalia :

vulva Female External Genitalia (Vulva)

Mons pubis and labia majora :

outer limits of vulva

contain sebaceous and apocrine sweat glands

Labia minora :

thin folds around the vestibule

Vestibule :

central space

has openings of urethra and vagina

Clitoris :

small erectile protuberance in vestibule

equivalent to the penis Glands of the Vestibule

Paraurethral (Skenes ) glands :

discharge into urethra

near external opening

Bartholins glands :

secrete into vestibule

near vaginal entrance Hormonal Regulation of the

Female Reproductive Cycle

Involves secretions of

hypothalamus , anterior pituitary

and gonads

Forms a complex pattern that

coordinates ovarian and uterine

cycles Functions of Estrogen

Maintains function of reproductive organs

Maintains female secondary sex characters:

> hair distribution, voice, fat distribution,

Affects CNS activity (especially in hypothalamus, where

estrogens increase the sexual drive)

Initiates repair and growth of endometrium

Stimulates bone and muscle growth Body Temperature & Ovulation

Just before ovulation :

estrogen dominates

basal body temperature declines by 1 C

Day after ovulation :

progesterone dominates

temperature rises by 1 CBody Temperature & Ovulation

Just before ovulation :

estrogen dominates

basal body temperature declines by 1 C

Day after ovulation :

progesterone dominates

temperature rises by 1 CCoitus (Copulation)

Sexual intercourse:

introduces semen into female reproductive tract

Coordinated by sympathetic and parasympathetic divisions of

ANS

Sperms find their way for  Impotence (ED)

Male sexual dysfunction:

an inability to achieve or maintain an erection

caused by:

psychological factors

physical factors Sexually Transmitted Diseases (STDs)

aka sexually transmitted infections (STI)

Infections transferred by sexual intercourse

Examples:

bacterial :

gonorrhea, syphilis, chancroid, pelvic inflammatory disease (PID)

viral :

herpes, genital warts, AIDS

fungal :

candidiasis

protozoal :

trichomoniasis Aging & the Reproductive System

Male reproductive system:

changes associated with andropause

occur gradually, over longer time period

Female reproductive system:

changes associated with menopause Menopause

Time that ovulation and menstruation cease

Typically occurs around age 4555

Hormonal changes:

levels of estrogens and progesterone

levels of GnRH, FSH, and LH

Premature menopause :

depletion of ovarian follicles before age 40 Effect of Decreased Estrogen Levels

Reduction in uterus and breast size

Thinning of urethral and vaginal epithelia

Osteoporosis Relationships between Reproductive & Other Systems Development

Transcript for:Overview of Reproductive System Anatomy

Transcript for:
Overview of Reproductive System Anatomy