anatomi-fisiologi repro pria -farmasi-2014

Sistem Reproduksi Pria

C h a p t e r27 2012 Pearson Education, Inc.Tujuan PembelajaranMenjelaskan Struktur Sistem reproduksi priaMenjelaskan fungsi Sistem reproduksi pria

Reproductive SystemReproductive system functions in gameteProductionStorageNourishmentTransportFertilization Fusion of male and female gametes to form a zygoteReproductive system includes:Gonads (testes, ovaries)DuctsAccessory glands and organsExternal genitaliaMales and FemalesMalesTestes produce spermatozoaExpelled from body in semen during ejaculationFemalesOvaries produce oocytesImmature ovumTravels along uterine tube toward uterusVagina connects uterus with exterior of bodyMale Reproductive SystemPathway of spermatozoaEpididymisDuctus deferensEjaculatory ductAccessory organsSeminal vesiclesProstate glandBulbourethral glandsScrotal sac encloses testesPenisFigure 26.1 The Male Reproductive SystemFigure 26.1

Descent of the testesMovement of testes through inguinal canal into scrotumOccurs during fetal developmentTestes remain connected to internal structuresSpermatic cordsThe testesFigure 26.2 The Descent of the TestesFigure 26.2a

Figure 26.2 The Descent of the TestesFigure 26.2bFigure 26.3Figure 26.3 The Male Reproductive System in Anterior View

Musculature of scrotal sacDartos muscle wrinkles scrotal sacCremaster muscle pulls sac close to bodyTestes anatomyTunica albuginea surrounds testisSepta extend from tunica albuginea to epididymusLobulesMale AnatomyIn seminiferous tubulesInterstitial cells between seminiferous tubulesSecrete sex hormonesSperm pass through rete testisEfferent ductules connect rete testis to epididymusSperm productionFigure 26.4 The Structure of the TestesFigure 26.4

Seminiferous tubules Contain spermatogoniaStem cells involved in spermatogenesisContain sustentacular cellsSustain and promote development of spermSpermatogenesis

Figure 26.5 The Seminiferous TubulesFigure 26.5a, b

Figure 26.5 The Seminiferous TubulesFigure 26.5cFigure 26.6Figure 26.6 Chromosomes in Mitosis and Meiosis

Spermatogenesis involves three processesMitosis Meiosis Spermiogenesis SpermatogenesisFigure 26.7 SpermatogenesisFigure 26.7

Each spermatozoon has:HeadNucleus and densely packed chromosomesMiddle piece Mitochondria that produce the ATP needed to move the tailTail The only flagellum in the human body Anatomy of spermatozoon

Figure 26.8Figure 26.8 Spermiogenesis and Spermatozoon StructureTestes produce mature spermatozoaSperm enter epididymusElongated tubule with head, body and tail regionsMonitors and adjusts fluid in seminiferous tubulesStores and protects spermatozoaFacilitates functional maturation of spermatozoaMale reproductive tractFigure 26.9 The EpididymusFigure 26.9

Begins at epididymusPasses through inguinal canalEnlarges to form ampullaEjaculatory duct at base of seminal vesicle and ampullaEmpties into urethraDuctus deferens AKA vas deferensUrinary bladder to tip of penisThree regionsProstaticMembranousPenileUrethraSeminal vesicles Active secretory gland Contributes ~60% total volume of semenSecretions contain fructose, prostaglandins, fibrinogenAccessory glandsProstate glandSecretes slightly acidic prostate fluidBulbourethral glandsSecrete alkaline mucus with lubricating propertiesAccessory glandsFigure 26.10a-eFigure 26.10 The Ductus Deferens and Accessory Glands

Typical ejaculate = 2-5 ml fluidContains between 20-100 million spermatozoa per mlSeminal fluidA distinct ionic and nutritive glandular secretionContents of SemenMale external genitalia consist of the scrotum and the penisSkin overlying penis resembles scrotumPenisContains three masses of erectile tissue2 corpora cavernosa beneath fascia1 corpus spongiosum surrounding urethraDilation of erectile tissue produces erectionExternal genitalia

Figure 26.11Figure 26.11 The PenisFSH (Follicle stimulating hormone)Targets sustentacular cells to promote spermatogenesisLH (leutinizing hormone)Causes secretion of testosterone and other androgensGnRH (Gonadotropin releasing hormone)Testosterone Most important androgenHormones and male reproductive functionFigure 26.12Figure 26.12 Hormonal Feedback and the Regulation of the Male Reproductive Function

Arousal Leads to erection of the penis Parasympathetic outflow over the pelvic nervesEmission and ejaculation Occur under sympathetic stimulation Results in semen being pushed toward external urethral openingDetumescence Subsidence of erection Mediated by the sympathetic nervous systemMale sexual functionLevels of circulating testosterone begin to declineFSH and LH levels riseGradual reduction in sexual activityMale climacteric