Is coordinated by complex neural reflexes Using sympathetic and parasympathetic divisions of ANS Male sexual arousal Leads to increase in parasympathetic outflow over pelvic nerves which leads to ID: 1042723
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2. 28-4 Sexual FunctionMale Sexual Function Is coordinated by complex neural reflexesUsing sympathetic and parasympathetic divisions of ANSMale sexual arousalLeads to increase in parasympathetic outflow over pelvic nerves, which leads to erection
3. 28-4 Sexual FunctionMale Sexual Stimulation Initiates secretion of bulbo-urethral glandsLubricates penile urethra and surface of glansLeads to coordinated processes of emission and ejaculation
4. 28-4 Sexual FunctionEmission Occurs under sympathetic stimulationPeristaltic contractions of ampullaPush fluid and spermatozoa into prostatic urethraSeminal glands contractIncreasing in force and duration Peristaltic contractions in prostate glandMove seminal mixture into urethraSympathetic contraction of urinary bladder and internal urethral sphincterPrevents passage of semen into bladder
5. 28-4 Sexual FunctionEjaculation Occurs as powerful, rhythmic contractionsIn ischiocavernosus and bulbospongiosus musclesThat stiffen penisPush semen toward external urethral openingCauses pleasurable sensations (orgasm)Followed by subsidence of erectile tissue (detumescence)
6. 28-4 Sexual FunctionImpotence Also called male sexual dysfunctionIs an inability to achieve or maintain an erectionCaused by physical or psychological factors
7. 28-4 Sexual FunctionFemale Sexual FunctionParasympathetic activation leads to:Engorgement of erectile tissuesIncreased secretion of cervical mucous glands and greater vestibular glandsBlood vessels in vaginal walls fill with blood Fluid moves from underlying connective tissuesTo vaginal surfaces
8. 28-4 Sexual FunctionFemale Orgasm Is accompanied by:Peristaltic contractions of uterine and vaginal wallsRhythmic contractions of bulbospongiosus and ischiocavernosus muscles
9. 28-4 Sexual FunctionSexually Transmitted Diseases (STDs) Are transferred by sexual intercourseInclude bacterial, viral, and fungal infectionsPelvic inflammatory disease (PID)AIDSGonorrheaSyphilisHerpesGenital wartsChancroid
10. 28-5 Effects of Aging on the Reproductive SystemEffects of AgingFemale reproductive systemChanges associated with menopauseMale reproductive systemChanges associated with male climacteric (andropause) Occur gradually, over longer time period
11. 28-5 Effects of Aging on the Reproductive SystemMenopause Is the time that ovulation and menstruation ceaseTypically occurs around age 45–55Circulating concentrations of estrogens and progesterone declineProduction of GnRH, FSH, and LH rises sharply
12. 28-5 Effects of Aging on the Reproductive SystemPerimenopauseThe interval immediately preceding menopauseOvarian and uterine cycles become irregularDue to shortage of primordial folliclesEstrogen levels declineOvulation is not triggered
13. 28-5 Effects of Aging on the Reproductive SystemDecline in Estrogen Levels Leads to: Reduction in uterus and breast sizeThinning of urethral and vaginal epitheliaReduction in bone deposition (osteoporosis)
14. 28-5 Effects of Aging on the Reproductive SystemThe Male Climacteric (Andropause)Is the period of declining reproductive function Circulating testosterone begins to declineBetween ages 50 and 60Circulating FSH and LH increaseSperm production continuesSexual activity gradually decreasesWith declining testosterone levels
15. 28-6 Sex Hormones and HomeostasisMalesSperm count must be adequateSemen must have correct pH and nutrientsErection and ejaculation must function properly
16. 28-6 Sex Hormones and HomeostasisFemalesOvarian and uterine cycles must coordinate properlyOvulation and oocyte transport must occur normallyEnvironment of reproductive tract must supportSurvival and movement of spermFertilization of oocyte
17. Table 28-1 Hormones of the Reproductive System
18. 28-6 Reproductive System IntegrationHuman Reproduction Requires normal function of multiple systemsReproductive systemDigestive systemEndocrine systemNervous systemCardiovascular systemUrinary system
19. Figure 28-26 System Integrator: The Reproductive System Body SystemBody SystemS Y S T E M I N T E G R A T O RReproductive SystemReproductive SystemCardiovascularRespiratoryLymphaticEndocrineNervousMuscularSkeletalIntegumentaryDigestiveUrinaryCardiovascularRespiratoryLymphaticEndocrineNervousMuscularSkeletalIntegumentaryPage 857Page 807Page 759Page 632Page 543Page 369Page 275Page 165DigestivePage 910UrinaryPage 992The Male Reproductive SystemFor all systems, the reproductivesystem secretes hormones witheffects on growth and metabolism.Accessory organ secretions mayhave antibacterial action that helpsprevent urethral infections in malesFigure 28-26 diagrams the functional relationships betweenthe reproductive system and the other body systems.In pregnant women, digestive organsare crowded by developing fetus,constipation is common, and appetiteincreasesChanges in respiratoryrate and depth occurduring sexual arousal, under control of thenervous systemLysozymes andbactericidal chemicals insecretions provide innatedefense againstreproductive tractinfectionsEstrogens may help maintain healthy vessels and slow development of atherosclerosisSteroid sex hormones and inhibininhibit secretory activities ofhypothalamus and pituitary glandSex hormones affect CNSdevelopment and sexual behaviorsReproductive hormones, especiallytestosterone, accelerate skeletalmuscle growthSex hormones stimulate growth andmaintenance of bones; sex hormonesat puberty accelerate growth andclosure of epiphyseal cartilagesReproductive hormones affectdistribution of body hair andsubcutaneous fat depositsCovers external genitalia; providessensations that stimulate sexualbehaviors; mammary glandsecretions provide nourishment fornewbornPelvis protects reproductive organsof females, portion of ductusdeferens and accessory glands inmalesContractions of skeletal muscleseject semen from male reproductivetract; muscle contractions duringsexual act produce pleasurablesensations in both sexesControls sexual behaviors and sexualfunctionHypothalamic regulatory hormones andpituitary hormones regulate sexualdevelopment and function; oxytocinstimulates smooth muscle contractionsin uterus and mammary glandsDistributes reproductive hormones;provides nutrients, oxygen, andwaste removal for fetus; localblood pressure changesresponsible for physicalchanges during sexual arousalProvides IgA for secretionsby epithelial glands; assistsin repairs and defenseagainst infectionProvides oxygen and removes carbondioxide generated by tissues ofreproductive systemProvides additional nutrients requiredto support gamete production and (inpregnant women) embryonic and fetaldevelopmentUrethra in males carries semen toexterior; kidneys remove wastesgenerated by reproductive tissuesand (in pregnant women) by agrowing emtryo and fetusThe REPRODUCTIVE System