The Reproductive System The female The Functions Produce

The Reproductive System “The female”

The Functions • Produce female gametes to pair with the male’s • To provide protection and nourishment to developing offspring for several years • Secondary sex characteristics – Hip/waist ratio of. 7 – Development of breasts

Female Organs Essential Organs • Gonads in female are the ovaries • Female gametes are the ova, oocyte Accessory Organs • Uterine (fallopian) tubes • Uterus • Vagina • Vulva (external genitals) • Mammary glands http: //www. visiblebody. com/Brief. Overview. Male. Female. Movie

Perineum • Is in danger of being torn in childbirth which can lead to many complications • An episiotomy is sometimes done to prevent the damage caused by tearing

The Ovaries • Puckered almond-like shape • Anchored to the uterine wall by mesovarian ligaments • The distal portions of the uterine tubes cup the ovaries

Oogenesis • Beneath the epithelial layer of the ovaries are ovarian follicles • Each ovarian follicle contains an immature sex cell called an oocyte • Oocytes are surrounded by hormone releasing follicular (granulosa) cells • The oocyte goes through various stages until it is released as a mature ovum • Oogenesis results in only one viable ovum and 3 polar bodies

Functions of Ovaries • Ovary functions result in ovulation, release of ovum into the uterine tube • Ovaries secrete estrogen and progesterone, these regulate reproductive functions • Ovulation alternate between ovaries each month

Uterus • Pear-shaped in a woman who has never been pregnant • The top, wide part is referred to as the body • The bottom, neck part is referred to as the cervix • The bulge on top of the body is called the fundus

Uterus Layers • • • Endometrium – The inner lining that secretes mucus that acts as a barrier to sperm except during ovulation when it becomes slippery to facilitate sperm movement – Two upper layers are shed during menstruation and after delivering a baby Myometrium – Thick, smooth muscular layer – Smooth muscle is blended with connective tissue to give it elasticity and strength Parietal peritoneum – External layer that partially covers the uterus

Uterus Position • Normal position is anterior to rectum and posterior to bladder • The body normally rests superior to the bladder meeting the vagina at a right angle • Retroflexion is a backward tilt that can result in a prolapsed uterus

Uterine Functions • If fertilization occurs, the developing cell implants in the uterus (womb) • Specialized glands nourish the offspring until a placenta can develop • The placenta allows for the exchange of nutrients between mother and offspring • The myometrium contracts during childbirth • If no fertilization occurs then endometrium will shed during menstruation

Uterine Tube • • Also called fallopian tubes or oviducts There are three divisions – Isthmus extends out from uterus – Ampulla is the intermediate portions – Infundibulum is fringe-like projection that cups ovaries and opens into the peritoneal cavity, finger-like projections (fimbriae) collect the ovum • • Uterine tubes are the site of fertilization Tubal ligations prevent ovum from entering the oviducts

Ectopic Pregnancy • Ectopic pregnancy is any pregnancy that occurs outside the uterus

Vagina • Tubular organ that lies anterior to rectum and posterior to the bladder and urethra • It is approximately 7 to 8 cm long and capable of great distention • It is collapsible, lined with mucus membranes arranged in rugae

Vaginal Functions • Receptacle for sperm • Lower portion of birth canal • Transport of blood and tissue shed during menstruation

Vulva • Refers to external genitalia – Mons pubis- skin-covered layer of fat over the symphysis pubis – Labia majora- “large lips”, contain sweat and sebaceous glands, are homologous to the scrotum – Labia minora- “small lips” located medial to labia majora, the area between labia minora is referred to as the vestibule – Clitoris- homologous to the glans in the penis and is also covered by a prepuce – Urinary meatus- urinary opening situated between the clitoris and vaginal opening

The Breasts • Estrogen and progesterone stimulate the development of mammary ducts and secreting cells during puberty • Secreting cells are arranged in grape-like clusters whose ducts converge at the nipple • The ducts enlarge slightly into lactiferous sinus before reaching the nipple • The areola is the dark pigmented area around the nipple that contains many sebum glands

Self-Breast Exams • Should be done monthly a few days after the menstrual cycle • Look for unusual changes in appearance and color, especially dimpling or puckering of skin • Feel the breast using a pattern so that you cover all the areas • Sometime to the shower makes it easier to detect changes • Second most common cancer is young women, second most deadly

Lactation • Estrogen during pregnancy acts permissively on progesterone to prepare the breasts for lactation • Estrogen inhibits the function of prolactin • Shedding of placenta cuts off estrogen which stimulates the release of prolactin • Suckling of a baby stimulates prolactin and oxytocin • Milk secretion begins on the third or fourth day after delivery • Colostrum is yellowish secretion that is released before milk • Oxytocin stimulates the ejection of milk into the ducts

Benefits of Lactation • Perfect proportions of proteins, fats, calcium, vitamins and other nutrients • Passive immunity is conferred through mother’s antibodies in milk and colostrum • Enhances emotional bond between mother and child as well as further psychological development • Has been linked to – decreased allergies later in life – increased IQ – decreased risk of obesity

Ovarian Cycle • Before birth precursor cells undergo partial meiosis • After birth the female has many primary follicles each containing a oocyte • Once a month normally one oocyte migrates to the surface of the ovary and is released during ovulation • The ruptured follicle, called to corpus luteum, swells and begins to release estrogen and progesterone for 7 to 8 days • This process occurs 14 days before the next menstrual cycle

Menstrual Cycle Day 1 -5 – Menses or menstrual period Day 6 -13 – Post menstrual, post ovulatory phase – Increased estrogen levels cause mucus to become elastic Day 14 (28 day cycle) – Ovulation occurs – There is a decrease in basal body temp right before ovulation Day 15 -28 – Luteal phase or secretory phase – Corpus luteum secretes hormones during this phase

Menarche and Menopause • Menarche, menstration, usually begins around age 13 • Menses last for approximately 3 decades • Menopause begins between ages 45 -50 • Follicular cells are no longer responsive to estrogen