Female Reproductive System PDF

FEMALE SYSTEM - 1 Internal genitalia Ovary: primary female reproductive organ Produce gametes: ova Produce sex hormones: estrogen and progesterone Ovarian follicles: each follicle consists of an immature egg called an oocyte Number of eggs are determined at birth Born with 7 million oocytes At puber...

FEMALE SYSTEM - 1 Internal genitalia Ovary: primary female reproductive organ Produce gametes: ova Produce sex hormones: estrogen and progesterone Ovarian follicles: each follicle consists of an immature egg called an oocyte Number of eggs are determined at birth Born with 7 million oocytes At puberty about 250,000 remain FEMALE SYSTEM - 2 Internal genitalia Duct system Uterine tubes (fallopian tubes or oviducts) Receive ovulated oocyte No contact with ovary Oocyte moved to uterus by currents of peritoneal fluid caused by movement of fimbriae Nonciliated cells produce secretions to keep oocyte and sperm (if present) moist and nourished FEMALE REPRODUCTIVE ANATOMY INTERNAL GENITALIA - 1 Duct system Uterus: hollow, thick-walled, muscular organ Functions: a. retain b. receive c. nourish a fertilized ovum Three layers Perimetrium: outermost serous layer Myometrium: middle smooth muscle layer that expels the baby during birth Endometrium: mucosal lining of the uterine cavity INTERNAL GENITALIA - 2 INTERNAL GENITALIA - 3 INTERNAL GENITALIA – 4 Duct system Vagina: birth canal Functions: a. passageway for delivery of infant b. passageway for menstrual flow Resident bacteria make the vagina acidic a. keeps the vagina healthy b. keeps it free from infection EXTERNAL GENITALIA - 1 Vulva Mons pubis Labia majora Labia minora Vestibule Recessed area containing: a. external openings of the urethra and vagina b. greater vestibular glands: release mucus into the vestibule c. clitoris: composed largely of erectile tissue EXTERNAL GENITALIA - 2 EXTERNAL GENITALIA - 3 Mammary glands: produce milk to newborn Present in both males and females OOGENESIS - 1 Before birth: ovum production begins Each month from puberty to menopause Several oocytes released each month Usually only one enters meiosis I Secondary oocyte: The larger cell containing nearly all the cytoplasm of the primary oocyte after division in meiosis I First polar body: The smaller cell after meiosis I Secondary oocyte pauses in Metaphase II If not penetrated = it deteriorates If penetrated = it quickly completes meiosis II Producing: one large ovum OOGENESIS - 2 OVARIAN CYCLE Follicle phase: Primordial follicle → primary follicle → secondary follicle → late secondary follicle → vesicular follicle → ovulation Ovulation: release of the secondary oocyte Marks the end of the follicular phase and the start of the luteal phase Luteal stage: Granulosa cells of the vesicular follicle form an endocrine structure called the corpus luteum Corpus luteum secretes progesterone and some estrogen If no pregnancy: the corpus luteum starts degenerating OVARIAN AND MENSTRUAL CYCLES ESTROGEN AND PROGESTERONE FLUCTUATIONS DURING OVARIAN CYCLE PITUITARY HORMONE CONTROL OF OVARIAN CYCLE SUMMARY FEMALE SEXUAL RESPONSE Similar to male without ejaculation There is a no latent period in women like men Orgasm is not required for reproduction MENOPAUSE Fertility in the female peaks in the later 20s and declines slowly until 35 on average, after which it declines rapidly After a full year without menses, a woman is said to have completed menopause Reduced levels of estrogen and progesterone lead to several symptoms during menopause Post-menopause, lowered estrogen can lead to other issues with female overall health PUBERTY SEXUAL DETERMINATION - 1 Genetic determination One pair of chromosomes are the sex chromosomes (X or Y) Females = XX Males = XY If fertilized with X from Mom and X from Dad = female X from Mom and Y from Dad = male Y has SRY gene is the sex-determining region on the Y chromosome The master switch that initiates testes development SEXUAL DETERMINATION - 2 Reproductive system differentiation 5 – 6 weeks: Sexually indifferent 7 – 8 weeks XY individuals begin to show male parts 8 – 9 weeks XX individuals begin to show female parts SEXUAL DIFFERENTIATION