Lecture 22
Female Reproductive System
 Ovaries o These gonads produce __________ cells and sex hormones o Almond-shaped and measuring about 3 cm long, 1.5 cm wide and 1 cm thick o Medulla is a zone of fibrous connective tissue containing arteries and veins o Cortex is the site of the ovarian __________________
 Each follicle consists of one developing ovum surrounded by numerous small follicular cells o Ovaries are held in place by tissue ligaments
 The ovaries are attached to the uterus by the ovarian
________________
 At the opposite ends, the ovaries are attached to the pelvic wall by suspensory ligaments
 The anterior margin of the ovary is anchored by a peritoneal fold called the ___________________
 This extends to a sheet of peritoneum called the broad ligament which runs along the side of the uterus
 Oogenesis and ova o The production of female gametes is called oogenesis o It employs meiosis to produce haploid gametes o It differs from spermatogenesis in that
 it is not a ____________________ process.
 it occurs in a rhythm called the ovarian cycle
 it produces only one functional gamete
 The other daughter cells are called polar bodies which die o In the (female) fetus, germ cells differentiate into oogonia which multiply until the fifth month of gestation
 They produce 6 to 7 million and then go into a state of
_________________ development until shortly before birth
 Some of them then transform into primary oocytes and go as far as early meiosis I
 Most primary oocytes degenerate before a girl is born
 2 million remain at birth
 By the onset of puberty, only 400,000 remain o This is the female’s ________________ supply of germ cells o During a woman’s reproductive years, about 20 to 25 oocytes and follicles begin to develop each month. o Normally, just one of these reaches maturity and ovulates, and the rest degenerate o The stages of oogenesis are accompanied by changes in the follicle
 The primary oocyte is initially enclosed in a primordial follicle

 A ________________ layer of squamous follicular cells surrounding the oocyte
 About 3 days before the menstrual period begins, pituitary secretion of FSH stimulates primordial follicles to develop into primary follicles
 The follicular cells thicken into a cuboidal epithelium, multiply, and become stratified
 One of the primary follicles forms a fluid-filled cavity called an
_________________
 The follicle is then called a secondary follicle
 The secondary follicle enlarges to as much as 2.5 cm in diameter and bulges like a balloon
 This is called a mature follicle (or a graafian follicle)
 The release of the oocyte from the follicle is called ovulation
 It typically occurs at about day 14 of the ovulation cycle
 When the oocyte is expelled, the follicle collapses and becomes a structure called a corpus _________________
 The corpus luteum secretes a large amount of progesterone, which stimulates the uterus to prepare for possible pregnancy
 Uterine tubes o The ovulated oocyte travels through this tube to reach the uterus o Also called the oviduct or ____________________ tube o At the distal end of the tube it has feathery projections called fimbriae that direct the egg into the tube o The wall of the tube has smooth muscle that produces contractions to direct the egg towards the uterus o The mucosa has ciliated cells that direct the egg towards the uterus
 Uterus o This is a thick ____________________ chamber that opens into the roof of the vagina o It usually tilts forward over the urinary bladder o Its functions:
 Harbor the fetus
 Provide it with a source of nutrition
 Expel the fetus at the end of gestation o It’s somewhat pear-shaped
 It has a broad superior curvature (the dome-shaped part) called the
_________________
 It had a midportion called the body
 It has a narrow inferior portion called the cervix
 The opening through the cervix to the vagina is the cervical canal o The uterine wall
 The myometrium is composed mainly of bundles of smooth muscle

 The ____________________ is the inner lining
 The stramum functionalis is shed each menstrual period
 The stratum basalis stays behind an degenerates a new funtionalis in the next cycle
 Ligaments
 The broad ligament, cardinal ligament, uterosacral ligaments, and round ligament all hold the uterus in place
 Menstrual Cycle
 ___________________ phase – time of building the endometrial tissue from .5 mm thick to about 2 to 3 mm thick through mitosis
 Secretory phase – time of further thickening, but as a result of accumulation of fluid rather than mitosis
 Premenstrual phase – period of endometrial degeneration occurring in the last 2 days of the menstrual cycle o Tissue and blood fall away from the uterine wall, forming menstrual fluid
 _________________ phase – begins when enough menstrual fluid has accumulated in the uterus that it begins to be discharged vaginally
 Vagina o This is a tube that allows for
 Discharge of menstrual fluid
 Receipt of the penis and semen
 The birth of a baby o It is thin-walled but very distensible o At the lower end is the _________________ , which stretches across the opening of the vagina
 The hymen may be ruptured by sexual intercourse, but is commonly ruptured before then in other ways o The lower end has vaginal rugae which stimulate the penis and help induce ejaculation
 External Genitalia o Collectively known as vulva o The mons pubis is the _________________ mound of adipose tissue overlying the symphysis pubis o The labia majora are a pair of thick folds of skin and adipose tissue
 Inferior to the mons pubis
 Between the thighs o The labia minora are thin folds of tissue medial to labia majora o The vestibule is the area enclosed by the labia minora o The clitoris is found at the anterior junction of the labia minora
 Its function is entirely __________________
 It’s the primary center of erotic stimulation o The vestibular bulbs are pairs of subcutaneous erectile tissues
 They are just deep to the labia majora

 They become congested with blood and cause the vagina to tighten somewhat around the penis o The vestibular __________________ are found next to the vagina
 They keep the vulva moist and provide lubrication during sexual intercourse
 Breasts and Mammary Glands o The breast is a mound of tissue overlying the pectoralis major o The mammary gland develops within the breast during pregnancy
 It remains active in the lactating breast
 At atrophies when a woman ceases to nurse o The breast has two principle regions
 The body – the conical to pendulous part
 At its apex is the nipple
 The ______________________ tail – the portion that extends toward the armpit o The areola is a circular colored zone that surrounds the nipple
 Dermal capillaries and nerves come closer to the surface here than in the surrounding skin
 It makes the area more sensitive and reddish in color
 In pregnancy, the areola and nipple may darken, to make them more visible to the nursing infant
 Sensory nerve fibers are important in triggering a milk ejection reflex when an infant nurses o Internally, the non-lactating breast is mostly adipose and collagenous tissue o Suspensory ligaments attach the breast to the dermis overlying the skin and to the fascia of the pectoralis major o When the mammary gland develops during pregnancy, it exhibits 15 to 20 lobes arranged radially around the ________________
 Each lobe is drained by a lactiferous duct
 Lactiferous ducts dilate to form a lactiferous sinus which opens into the nipple