Presentation on theme: "Male Reproductive System"— Presentation transcript:
1Male Reproductive System Unit 5: ReproductionMale Reproductive SystemFemale Reproductive System
2Label the following diagram BladderRectumVas deferensSeminal VesicleUrethraEjaculatory ductProstate glandPenisCowper’s glandGlans3% of boys are born with testes that have not descended properly – can be corrected surgicallyEpididymisPrepuce (Foreskin)TestisThe scrotum regulates the temperature of the testes.ScrotumSperm form best at 35oC.
3Label the following diagram Ureter (carries urine from kidney to bladder)BladderSeminal VesicleProstate glandCowper’s glandEpididymisVas deferensVasa (ductus) deferentiaTestesUrethraLink with pictures
5Wall of Seminiferous tubule Male TestesVas deferensInterstitial CellsIn between seminiferoustubules.Produce testosteroneepididymisSeminiferousTubulesWhere spermare madespermDevelopingFollicles (n)SpermSertoliCellFollicle (2n)Wall of Seminiferous tubuleNourishes sperm, secretes inhibin, spermatogenesis, stimulated by FSH and testosterone
7Testes Sertoli cells in Seminiferous tubules Interstitial cells Contain:Sertoli Cells (in seminiferous tubules)Secrete chemicals required for the nourishment and development of sperm cellsResponsible for spermatogenesis.Protection from man’s immune systemProduce inhibin hormone to slow sperm productionInfluenced by FSH (follicle stimulating hormone) from pituitary and by testosterone from interstitial cells.2. Interstitial Cells (b/w seminiferous tubules)Produce testosteroneInfluenced by LH (leutinizing hormone) from the pituitarySertoli cells in Seminiferous tubulesInterstitial cells
9Contains an enzyme to penetrate layers surrounding the ovum SpermHeadAcrosome and nucleus(23 chromosomes)MiddleMitochondriafor energyContains an enzyme to penetrate layers surrounding the ovumTailFlagellumfor swimmingSperm moves at a rate of 3mm/hourLife span of a sperm cell:In the epididymis - many yearsIn semen – at body temperature, daysStored at -100oC - many yearsWatch sperm swim
10Pathway of Sperm The Great Sperm Race TestesVas deferensEjaculatory ductEpididymisVas deferensEjaculatory DuctUrethraEpididymis
11Scrotum and Epididymis - Skin and muscle covering the testes- Allows sperm to develop at optimal temperature (35oC)ScrotumEpididymis- storage and maturation of sperm- the immune system destroys the “bad” sperm- develop a flagellum to swim.Epididymis
12Vas Deferens and Ejaculatory Duct Ductus (Vas) Deferens – carries sperm from epididimus-> ejaculatory ductVas deferensEjaculatory ductEjaculatory Ductregulates the movement of semen into the urethra.In Latin, the term “deferens” means “to carry”(A sphincter regulates the removal of urine from the bladder.)
13Penis and Urethra Urethra - carries semen (reproductive system) and urine (excretory system).
14an acronym to remember the order Seminal FluidStudent Price Cardan acronym to remember the orderSecreted by Accessory Glands:Seminal VesicleProstate gland3/4 ml/ejaculate contains 500 million spermCowper’s gland
15Seminal Fluid (Semen) 1) Seminal vesicles - 60% of total fluid Contains fructose for energyand Prostaglandins which cause rhythmic contractions of the smooth muscles in female, which help sperm move up the uterus.Seminal VesicleProstate gland3/4 ml/ejaculate contains 500 million spermCowper’s gland
16Seminal Fluid (Semen) 2) Prostate gland: alkaline buffer and mucus that protects sperm against acidic environments in the urethra and the vagina.Increases mobility of spermSeminal VesicleProstate gland3/4 ml/ejaculate contains 500 million spermCowper’s gland
17Prostate CancerProstate cancer – Due to genetics, diet and lifestyle. Symptoms: Difficulty urinating, blood in urine, erectile dysfunction. Diagnose with a rectal exam. (Start testing at ~age 40.)Prostate gland3/4 ml/ejaculate contains
19Sperm + seminal fluids = semen Seminal Fluid (Semen)3) Cowper’s gland:Secretes a mucus and alkaline buffer prior to ejaculationprotects against acid in urine and increases mobility.May contain sperm (reason for high failure rate of withdrawal method)Seminal VesicleProstate glandCowper’s gland3/4 ml/ejaculate contains 500 million spermSperm + seminal fluids = semen
20SemenIn one ejaculate there is about 3 – 4 mL of fluid and about 40 – 100 million sperm cells per mL(Note: at least a few dozen must reach the egg to ensure fertilization!)Seminal VesicleProstate gland3/4 ml/ejaculate contains 500 million spermCowper’s gland
21Penis Delivers semen to female vagina Arterioles dilate increase blood flow Fills with blood to become erectCompresses veins that carry blood away from penis pressure builds erectionDilation of the arteries (erection) of the penis is under the influence of the parasympathetic nervous system.
22The Great Sperm RaceEjaculation: the release of semen through the urethraEjaculation is accomplished by the contraction of the vas deferens, the prostate and the muscles at the base of the penis, under the influence of the sympathetic nervous system.Refractory period: period of time that must pass prior to a second erection.
25How is a penis like a camera? Because for both you just Point and Shoot...Point = Parasympathetic… controls erectionsShoot = Sympatheticcontrols ejaculations
26Impotency Impotency: inability to produce or maintain an erection. Possible causes:- hormone imbalance- problem with parasympathetic nerves (damage)-drugs / alcohol / smoking-Stress
27Puberty in boysPuberty is when the reproductive system completes its development and becomes fully functionalPuberty begins when the hypothalamus begins releasing gonadotropin releasing hormone (GnRH)GnRH acts on the anterior pituitary to produce FSH and LHPuberty begins
28Hormonal Control Testosterone- stimulates: Brain spermatogenesis primary characteristics (reproductive organs)secondary characteristics (deepening of voice, facial and pubic hair, muscle growth)Inhibin – produced by the Sertoli cells to inhibit FSH production which slows sperm productionMasterGland
30Andropause Decline in testosterone production in men Happens around age 40Results in depression, fatigue, drop in sperm production, and loss of muscle and bone massTreatment: testosterone supplements, exercise
31Male Reproductive System (within testes – not visible here) Mini-Review1. Arrange the following structures in the order that sperm passes through them:vas deferensurethraepididymisseminiferous tubulesejaculatory duct1. vas deferens5. ejaculatory duct3. epididymis2. urethra4. seminiferous tubules(within testes – not visible here)4, 3, 1, 5, 2
32Male Reproductive System Mini-Review2. What is the significance of the acrosome of the sperm?A: The acrosome contains enzymes needed to help the sperm penetrate through the protective layer surrounding a female egg
33Male Reproductive System Mini-Review3. What is the difference between interstitial cells and Sertoli cells?Interstitial cells:Located between seminiferous tubulesSecrete testosteroneSertoli cells:Located inside seminiferous tubulesNourish and support developing spermResponsible for spermatogenesisRelease inhibin
34Male Reproductive System Mini-Review3. Where are sperm made?Seminiferous TubulesFollicle cells are stimulated by the sertoli cells to undergo meiosis.
35Label the following diagram fallopian tube (oviduct)ureterovaryfimbriaeuterusbladdercervixurethraclitorisvaginalabium minoralabium majora
36Label the following diagram fallopian tube (usual site of fertilization)Endometrium(uterine lining)Fimbriae (catches the egg)Uterus (usual site of implantation)Ovary (oogenesis, estrogen and progesterone)Cervix (opening of uterus)Vagina (birth canal)
37Ovaries – site of oogenesis Females have 2 ovaries, which alternate each month to produce an egg/ovum (oogenesis).Follicles: ovum (egg) (female gametes) & accessory cells (“Granulosa cells”), secrete estrogenCorpus luteum: secretes hormones (Estrogen & Progesterone).Fallopian tubeovaryOvaries contain ~ 400,000 egg cells, but only ~ 400 actually mature between the ages of 12 – 50.
38Ovum (egg) NOVA: The Egg’s Journey sperm Ovary The egg is larger than sperm because the cytoplasm in the egg has to provide enough nutrients for 5 days if the egg is fertilized.Add characteristics of the ovumspermOvaryThe ovum lives for 24 hours after ovulation.NOVA: The Egg’s Journey
39Ovulation - When a follicle matures, it ruptures, releasing the ovum Fimbrae - picks up ovum from ovary (finger-like extensions of fallopian tube)Fallopian tube (Oviducts) passage from ovary to uterus; site of fertilizationFallopian tubeFimbriaeovary
40Uterus Uterus – site of embryo development, two layers: EndometriumUterus – site of embryo development, two layers:endometrium – nourishes embryo; shed during menstruation; blood vessel richMyometrium – muscular layerCervix – muscular opening to uteruscells constantly shed and replacedVagina – entrance for the penis as well as birth canalUteruscervixvaginaUterus – pear shape and sizeA pap smear checks for changes in the cells of the cervix. Changes may indicate infection, unhealthy cervical cells, or cervical cancer (can be caused by HPV(genital warts).
41Fertilization and Implantation Pathway for sperm:vaginacervixuterusFallopian tubeFallopian tubeUteruscervixFertilization usually occurs in the fallopian tubes and implantation occurs in the uterus.vagina
42Puberty in GirlsAt puberty, the hypothalamus releases gonadotropin releasing hormone (GnRH)GnRH activates the anterior pituitary to release FSH and LHFSH secretions are carried by the blood to the ovary where follicle development is stimulated.The follicles within the ovary secrete estrogen into the blood which stimulates the development of the secondary female characteristics: breasts, hair, wider hips.
43Female Reproductive Goals Develop follicle (egg)Develop EndometriumOvulateFertilize and ImplantMaintain Corpus Luteum and Endometrium(or shed to reset for next month)This is all accomplished via horomonal control!!!!!!!!
44Oogenesis: female meiosis! Begins before birth in ovaries…1 oogonia (2n) differentiates into 1 primary oocyte (2n)Meiosis I stops at Prophase I until pubertyAfter puberty…Each month, 1 primary oocyte finishes Meiosis I 1 secondary oocyte (1n) & 1 polar body (1n) Ovulation: secondary oocyte to fallopian tubesIF fertilized…secondary oocyte (1n) Meiosis II 1 Ovum (1n) & 1 polar body
45Menstrual Cycle Estrogen Progesterone and estrogen ~28 days longEstrogenFrom pituitary:FSHfolliclesImmature follicles (2n)Ovum (n)LHOvum released – ovulation (day 14)Girls have 2 million folicles, some will degenerate and are left by puberty, but only 400 will matureMeiosis II occursin fallopian tubeif fertilizedCorpus luteumProgesterone and estrogenOrder of hormones: FELP
46Hormones of the Menstrual Cycle GnRH: stimulated by high levels of E, inhibited by high E & P, causes FSH/LH releaseFSH: promotes follicle growthLH: promotes ovulation, corpus luteum formation E & P production
47Hormones of the Menstrual Cycle High E & P: promotes growth of endometrium, inhibits menstruation, inhibits GnRH inhibits FSH/LH inhibits follicle growth & ovulationdecrease of E & P triggers menstruation
48Hormones of the Menstrual Cycle hCG (“human chorionic gonadotropin hormone”):hormone secreted by embryo;prevents corpus luteum breakdown allows E & P to stay highpregnancy test: checks hCG in urine
49Follicle Corpus luteum Draw it!Hypothalamus(GnRH)Anterior pituitaryFSHLH(-) For FSH & LH(-)For FSHOvaryFollicleCorpus luteum(+)For LHEstrogenProgesterone and estrogen
50Menstrual Cycle: ~28 days 1. Flow phase (Day 1-5)endometrium is shed; follicle growth in ovaryEstrogen and progesterone levels are lowFlow Phase
51Menstrual Cycle: ~28 days 2. Follicular phase (Days 6-13):follicles grow and mature secrete Estrogenendometrium thickensStimulates GnRH & LHFollicularPhase
52Menstrual Cycle: ~28 days 3. Ovulation (Day 14): LH peaks causing secondary oocyte to burst from the follicle in the ovary into oviductOvulation
53Menstrual Cycle 4. Luteal Phase (Day 15-28) LH causes corpus luteum to develop from follicle corpus luteum secretes E&PEndometrium thickens and is maintained (progesteroneprevents contractions)Inhibits GnRH, LH & FSH (negative-feedback)Luteal Phase
54Menstrual Cycle: ~28 days 1.3.Label the hormones:FELPLH2.4.
56Hormone Review 1. FSH 2. Estrogen Target: follicles in the ovary Effect: Egg and estrogen2. EstrogenTarget: various cells, endometrium, hypothalamusEffect: development of 1o (reproductive organs) and 2o sexual characteristics (higher voice, larger hips); neg. feedback to decrease FSH; positive feedback to increase LH production; growth of endometrium(+) LH(-)(-)(-)
57Hormone Review 3. LH 4. Progesterone Target: follicle (ovulation) corpus luteumEffect: ovulation and progesterone and estrogen production4. ProgesteroneTarget: endometrium and hypothalamusEffect: thicken and maintain endometrium (inhibit contractions); negative feedback to stop FSH and LH(+) LH(-)(-)(-)
58Ovary LH from pituitary 4 3 1 2 Estrogen Corpus luteum Ovum Ovulation Progesterone and estrogen3LH from pituitaryOvumCorpus luteumOvulation1FSHFrom Pituitaryn2nFollicles2Estrogen
59Hormones Controlling X = _______ W = ______ Z = _______ Y = _______ MenstruationX = _______FSHW = ______EstrogenZ = _______LHY = _______Progesterone
61Low estrogen and progesterone. 1. The loss of the endometrium (a monthly occurrence during the reproductive phase of a female’s life) is termed ___________ and occurs over approximately ____ days.menstruation4-52. The endometrium is shed on a monthly basis but the immediate reason is because of :Low estrogen and progesterone.
63The numbered blocks represent hormones The numbered blocks represent hormones. Which hormone corresponds to each number?______ProgesteroneEstrogenFSHLH4321
64Which color represents which hormones? ProgesteroneBloodConcentration of Menstrual HormonesEstrogenLHFSH
65Answer the questions in your workbook using the following picture follicularWhich phase is dominated by estrogen?______________Which phase is dominated by progesterone? _____________The sharp rise in temperature signals what event?______________lutealovulation
67Menstrual Cycle: If pregnancy does not occur Estrogen and Progesterone levels dropEndometrium lining is shedBleeding occurs - menstruation
68For the first 3 months stimulated by hCG 1. Predict, with a sketch, what each diagram/graph should look like if a woman were to become pregnant at around day 21.Day 45For the first 3 months stimulated by hCGEstrogen and Prog. cause growth of the endometriumProgesterone prevents contractionsEndometrium forms part of placenta
69Menopause Occurs at around ~50 Ova are no longer produced This changes hormone production as wellSymptoms: hot flashes, high cholesterol and decreasing bone massHormone replacement therapy – women are given low doses of estrogen (some progesterone)But this has many side effects.Hot flashes – blood vessels dilate and constrict quicklyComplete the Menstrual Cycle Assignment
70Meiosis in Males and Females Males - SpermatogenesisLocation : testesFemales - OogenesisLocation: ovariesFollicle2NFollicle2NMeiosis 1Meiosis 1NNNNMeiosis 2Meiosis 2NNNNNNNN1 egg and 3 polar bodiesEgg (ovum) gets most of the cytoplasm. Polar bodies die and are absorbed by body.4 equal sperm
71150 – 300 million sperm travel though the cervix to the uterus. 100 – 500 sperm reach the oviductsRecall - egg has large cytoplasm, sperm very little cytoplasm. The cytoplasm of the egg has to nourish the zygote for approximately ________5 days
72In the Fallopian TubeMeiosis II2nfertilizationnn