female reproductive system - ms. kim€¦ · female hormones •estrogen–steroid hormone...
TRANSCRIPT
FemaleReproductiveSystem
Lesson10
LearningGoals
1. Whatarethefivehormonesinvolvedinthefemalereproductivesystem?
2. Understandthefour phasesofthemenstrualcycle.
HumanReproductiveSystem
FemaleReproductiveSystem
FemaleAnatomy
• Ovaries– producehormonesestrogenandprogesterone• Siteofeggdevelopmentandovulation
• Fallopiantubes(oviducts)– carryovumfromovarytouterus
• Uterus–organwherefetusdevelops
• Cervix– separatesvaginafromuterus
• Vagina– providesapassageforspermandmenstrualflow
OogenesisandOvulation• Oogenesis – productionofanegg
• Ovariescontainsmallgroupsofcellscalledfollicles• Folliclescontaintheeggandsecreteestrogen
• Duringovulation,theoocyteisreleased• Folliclecellsturnintothecorpusluteum
FemaleHormones
• Estrogen – steroidhormone• Maintenanceoffemalereproductivesystem• Developmentofsecondarysexcharacteristics(e.g.breastdevelopment,thegrowthofbodyhair,thewideningofthepelvis,andthedevelopmentofthesexdrive)
• Progesterone – steroidhormone• ControlledbyLHandFSH• Preparesuterusforimplantationoffertilizedegg
MenstrualCycle
• Preparationforpregnancy
1. Flowphase– day1-5
2. Follicularphase- day6-13
3. Ovulatoryphase- day14
4. Lutealphase- day15-28
FlowPhase(1-5)• Sheddingoftheendometriumliningmarkstheflowphase• Tissuethatlinestheuterinewall• Richwithbloodvessels
• LHandFSHreleasedbytheanteriorpituitary• Stimulatedbythehypothalamus(GnRH)• FSHstimulatestheeggtodevelop• Formsafollicle
• Endometriumliningbeginstogrowagainasthemenstrualflowceases
Follicularphase(6-13)
• FSH andLH causedevelopmentoffollicleswithinovary
• Estrogenissecreted• Estrogenhasanegativefeedbackeffectontheanteriorpituitary• InhibitsthesecretionofFSH
Ovulatoryphase(14)
• HypothalamusandpituitaryglandreleasesaburstofLHtotriggerovulation(LHsurge)
• Eggburstsfromovary• Follicleà corpusluteum
• Afterovulation,estrogenlevelsdeclineandprogesteronelevelsrise• ManyPMS(premenstrualsyndrome)symptomscan
ariseduetoahigherthannormalestrogentoprogesteroneratio
LutealPhase(15-28)
• Developmentofcorpusluteummarksthelutealphase• Corpusluteumproducesestrogenandprogesterone
• Progesterone– stimulatesendometriumandpreparesuterusforfertilizedegg• Inhibitsovulationanduterinecontractions
• Corpusluteumdegeneratesiffertilizationdoesnotoccur(duetolowlevelsofLH)• Estrogenandprogesteronedecrease• Causeweakcontractionsà endometriumpullsawayfromtheuterus(beginflowphase)
Pregnancy
• Iffertilizationoccurs,theeggwillimplantandembryowillbegintoreleasehCG (humanchorionicgonadotropin)
• hCGkeepscorpusluteumfrombreakingdown
• Corpusluteumpreventsmenstruationfromoccurringandkeepsestrogenandprogesteroneathighlevelstomaintainuterineliningandpreventmenstruation
HormonalControl
• Hypothalamus secretesGnRH–signalspuberty
• GnRHcausesanteriorpituitary toreleaseFSHandLH
• FSHcausesfollicle togrow
• LHcausesovulation andmaintenanceofcorpusluteum
•Negativefeedback• Highlevelsofestrogeninhibits releaseofFSH
•Positivefeedback• Highlevelsofestrogenstimulates releaseofLH
Homework
•CaseStudy:ChemicalEric
•HandoutQuestions