Mosby items and derived items © 2007, 2003 by Mosby, Inc.Slide 1 Chapter 32 Female Reproductive System

Mosby items and derived items © 2007, 2003 by Mosby, Inc.Slide 2 Overview of the Female Reproductive System  Function of the female reproductive system  The function of the female reproductive system is to produce offspring and thereby ensure continuity of the genetic code  It produces eggs, or female gametes, which each may unite with a male gamete to form the first cell of an offspring  It also can provide nutrition and protection to the offspring for up to several years after conception

Mosby items and derived items © 2007, 2003 by Mosby, Inc.Slide 3 Overview of the Female Reproductive System  Structural plan of the female reproductive system  Reproductive organs are classified as essential or accessory (Figure 32-1) Essential organs—gonads are the paired ovaries; gametes are ova produced by the ovaries—the ovaries are also internal genitals Essential organs—gonads are the paired ovaries; gametes are ova produced by the ovaries—the ovaries are also internal genitals Accessory organs Accessory organs  Internal genitals—uterine tubes, uterus, and vagina: ducts or duct structures that extend from the ovaries to the exterior  External genitals—the vulva  Additional sex glands such as the mammary glands

Mosby items and derived items © 2007, 2003 by Mosby, Inc.Slide 4 Overview of the Female Reproductive System  Perineum  The perineum is the skin-covered region between the vaginal orifice and the rectum  This area may be torn during childbirth

Mosby items and derived items © 2007, 2003 by Mosby, Inc.Slide 5 Ovaries  Location of the ovaries  Nodular glands located on each side of the uterus, below and behind the uterine tubes (Figure 32-2)  Ectopic pregnancy—development of the fetus in a place other than the uterus  Microscopic structure of the ovaries  Surface of the ovaries is covered by the germinal epithelium  Ovarian follicles contain the developing female sex cells (Figure 32-3)  Ovum—an oocyte released from the ovary

Mosby items and derived items © 2007, 2003 by Mosby, Inc.Slide 6 Ovaries  Functions of the ovaries  Ovaries produce ova—the female gametes  Oogenesis—process that results in formation of a mature egg (Figure 32-4)  The ovaries are endocrine organs that secrete the female sex hormones (estrogens and progesterone)

Mosby items and derived items © 2007, 2003 by Mosby, Inc.Slide 7 Uterus  Structure of the uterus (Figure 32-2)  Size and shape of uterus Pear-shaped, has two main parts—the cervix and the body Pear-shaped, has two main parts—the cervix and the body  Wall of uterus is composed of three layers—inner endometrium, middle myometrium, and outer, incomplete layer of parietal peritoneum  Cavities of uterus—cavities are small because of the thickness of the uterine walls The body cavity’s apex constitutes the internal os and opens into the cervical canal, which is constricted at its lower end and forms the external os that opens into the vagina The body cavity’s apex constitutes the internal os and opens into the cervical canal, which is constricted at its lower end and forms the external os that opens into the vagina  The blood to the uterus is supplied by uterine arteries

Mosby items and derived items © 2007, 2003 by Mosby, Inc.Slide 8 Uterus  Location of the uterus  Located in pelvic cavity between urinary bladder and rectum (Figure 32-1)  Position of uterus (Figure 32-5) is altered by age, pregnancy, and distention of related pelvic viscera  Descends, between birth and puberty, from the lower abdomen to the true pelvis  Begins to decrease in size at menopause

Mosby items and derived items © 2007, 2003 by Mosby, Inc.Slide 9 Uterus  Position of the uterus  Body lies flexed over the bladder  Cervix points downward and backward, joining the vagina at a right angle  Several ligaments hold the uterus in place but allow some movement

Mosby items and derived items © 2007, 2003 by Mosby, Inc.Slide 10 Uterus  Functions of the uterus  Part of reproductive tract, permits sperm to ascend toward uterine tubes  If conception occurs, an offspring develops in the uterus Embryo is supplied with nutrients by endometrial glands until the production of the placenta Embryo is supplied with nutrients by endometrial glands until the production of the placenta Placenta is an organ that permits exchange of materials between mother’s blood and fetal blood but keeps the two circulations separate Placenta is an organ that permits exchange of materials between mother’s blood and fetal blood but keeps the two circulations separate Myometrial contractions occur during labor and help push the offspring out of mother’s body Myometrial contractions occur during labor and help push the offspring out of mother’s body  If conception does not occur, outer layers of endometrium are shed during menstruation Menstruation is a cyclical event that allows the endometrium to renew itself Menstruation is a cyclical event that allows the endometrium to renew itself

Mosby items and derived items © 2007, 2003 by Mosby, Inc.Slide 11 Uterine Tubes  Uterine tubes are also called fallopian tubes, or oviducts  Uterine tubes are attached to the uterus at its upper outer angles and extend upward and outward toward sides of pelvis  Structure of uterine tubes  Consist of mucous, smooth muscle, and serous lining (Figure 32-6)  Mucosal lining is directly continuous with the peritoneum lining the pelvic cavity Tubal mucosa is continuous with that of the vagina and uterus, which means it may become infected with organisms introduced into the vagina Tubal mucosa is continuous with that of the vagina and uterus, which means it may become infected with organisms introduced into the vagina  Each uterine tube has three divisions: isthmus, ampulla, and infundibulum  Function of the uterine tubes  Serve as transport channels for ova and as the site of fertilization

Mosby items and derived items © 2007, 2003 by Mosby, Inc.Slide 12 Vagina  Vagina is a tubular organ located between the rectum, the urethra, and the bladder  Structure of the vagina  Collapsible tube capable of distention, composed of smooth muscle, and lined with mucous membrane arranged in rugae  Anterior wall is shorter than posterior wall because cervix protrudes into its uppermost portion  Hymen—a mucous membrane that typically forms a border around the vagina in young premenstrual girls

Mosby items and derived items © 2007, 2003 by Mosby, Inc.Slide 13 Vagina  Functions of the vagina  Lining of the vagina lubricates and stimulates the penis during sexual intercourse and acts as a receptacle for semen  Lower portion of the birth canal  Transports tissue and blood shed during menstruation to the exterior

Mosby items and derived items © 2007, 2003 by Mosby, Inc.Slide 14 Vulva  The vulva consists of the female external genitals: mons pubis, labia majora, labia minora, clitoris, urinary meatus, vaginal orifice, and greater vestibular glands (Figure 32-8)  Functions of the vulva  The mons pubis and labia protect the clitoris and vestibule  The clitoris contains sensory receptors that send information to the sexual response area of the brain  The vaginal orifice is the boundary between the internal and external genitals

Mosby items and derived items © 2007, 2003 by Mosby, Inc.Slide 15 Breasts  Location and size  The breasts lie over the pectoral muscles  Estrogens and progesterone control breast development  Breast size is determined by the amount of fat around glandular tissue (Figure 32-9)

Mosby items and derived items © 2007, 2003 by Mosby, Inc.Slide 16 Breasts  Function of the breasts  The function of mammary glands is lactation  Mechanism of lactation (Figure 32-10) Ovarian hormones make breasts structurally ready to produce milk Ovarian hormones make breasts structurally ready to produce milk Shedding of placenta results in decrease of estrogens and thus stimulates prolactin Shedding of placenta results in decrease of estrogens and thus stimulates prolactin Prolactin stimulates lactation Prolactin stimulates lactation  Lactation can provide nutrient-rich milk to offspring for up to several years from birth; some advantages are the following: Nutrients Nutrients Passive immunity from antibodies present in colostrum and milk Passive immunity from antibodies present in colostrum and milk Emotional bonding between mother and child Emotional bonding between mother and child

Mosby items and derived items © 2007, 2003 by Mosby, Inc.Slide 17 Female Reproductive Cycles  The female reproductive system has many cyclical changes that start with the beginning of menses  Ovarian cycle—ovaries from birth contain oocytes in primary follicles in which the meiotic process has been suspended; at the beginning of menstruation each month, several of the oocytes resume meiosis; meiosis will stop again just before the cell is released during ovulation (Figure 32-11)  Menstrual cycle (endometrial cycle) is divided into four phases: Menses Menses Postmenstrual phase Postmenstrual phase Ovulation Ovulation Premenstrual phase Premenstrual phase  Myometrial phase  Gonadotropic cycle

Mosby items and derived items © 2007, 2003 by Mosby, Inc.Slide 18 Female Reproductive Cycles  Control of female reproductive cycles  Hormones control cyclical changes  Cyclical changes in ovaries result from changes in gonadotropins secreted by pituitary gland (Figures and 32-13)  Cyclical changes in uterus are caused by changes in estrogens and progesterone (Figure 32-14)  Low levels of FSH and LH cause regression of the corpus luteum if pregnancy does not occur; this causes a decrease in estrogen and progesterone, which triggers endometrial sloughing of the menstrual phase  Control of cyclical changes in gonadotropin secretion is caused by positive and negative feedback mechanisms and involves estrogens, progesterone, and the hypothalamus’s secretion of releasing hormones

Mosby items and derived items © 2007, 2003 by Mosby, Inc.Slide 19 Female Reproductive Cycles  Importance of the female reproductive cycles  Ovarian cycle’s primary function is to produce an ovum at regular intervals Secondary function is to regulate endometrial cycle through estrogen and progesterone Secondary function is to regulate endometrial cycle through estrogen and progesterone  Function of endometrial cycle is to make uterus suitable for implantation of a new offspring  Cyclical nature of the reproductive system and the fact that fertilization will occur within 24 hours after ovulation mean that a woman is only fertile a few days of each month  Menstrual flow begins at puberty, and menstrual cycle continues for about three decades

Mosby items and derived items © 2007, 2003 by Mosby, Inc.Slide 20 The Big Picture: The Female Reproductive System and the Whole Body  The female reproductive system shares a special relationship with the following:  The urinary system because of their close proximity and because they share the vulva  The skeletal muscles in the perineum  The integumentary system because breasts are actually modifications of the skin