Chapter 28

Occasionally eggs are lost

1) disintegrate, or 2) implant in the abdominal wall and develop should it have been fertilized, resulting in an ectopic pregnancy.

Three main functions of ovaries

1. Production of immature female gametes (oocytes) 2. Secretion of female sex hormones (estrogens, progestins) 3. Secretion of inhibin, involved in feedback control of pituitary FSH

Vaginal Bacteria

A population of harmless resident bacteria. Supported by nutrients in cervical mucus creates acidic environment. Restricts growth of many pathogens

Isthmus

A short segment between ampulla and uterine wall. constricted area

Ovarian Cycle

After sexual maturation a different group of primordial follicles is activated each month

The Visceral Peritoneum of the Ovary

Also called germinal epithelium covers surface of ovary consists of columnar epithelial cells overlies tunica albuginea

Oogenesis

Also called ovum production begins before birth accelerates at puberty ends at menopause

Infundibulum

An expanded funnel near ovary. With fimbriae that extend into pelvic cavity. Inner surfaces lined with cilia that beat toward middle segment

Stroma

Are interior tissues of ovary superficial cortex deeper medulla gametes are produced in cortex

Primary oocytes

Are located in outer part of ovarian cortex near tunica albuginea in clusters called egg nest

Ovaries

Are small, almond-shaped organs near lateral walls of pelvic cavity. ovary has an outer cortex and an inner medulla. Interspersed throughout the cortex are many tiny egg sacs called ovarian follicles in different stages of development. A female is born with as many as two million follicles, but the number is reduced to 400,000 (200,000 in each) by the time of puberty. However, during the life of a female, no more than 400 mature eggs are produced.

Ovarian follicles

Are specialized structures in cortex of ovaries. Where oocyte growth and meiosis I occur

secondary tubules

As milk is secreted from these cells, it enters the

Uterine tubes

Carry oocytes to uterus - if sperm reaches oocyte, fertilization is initiated and oocyte matures into ovum

Estrogen

Causes uterine glands, blood vessels, and epithelium to change with phases of monthly uterine cycle. stimulates growth of the uterus and vagina; is necessary for egg maturation; is responsible for secondary sex characteristics; more body fat; larger pelvic girdle, and breast development.

ampullae

Close to the nipple the mammary ducts become expanded to form the

Vagina

Connects uterus with exterio. Is an elastic, muscular tube. Extends between cervix and vestibule 7.5-9 cm (3-3.6 in.) long Highly distensible cervix projects into vaginal canal fornix is shallow recess surrounding cervical protrusion lies parallel to: Rectum, posteriorly urethra, anteriorly

The Vaginal Wall

Contains a network of blood vessels and layers of smooth muscle Is moistened by: Secretions of cervical glands, water movement across ermeable epithelium

Two Characteristics of Meiosis

Cytoplasm of primary oocyte divides unevenly producing one ovum (with original cytoplasm) and two or three polar bodies (that disintegrate). Ovary releases secondary oocyte (not mature ovum) suspended in metaphase of meiosis II. Meiosis is completed upon fertilization

Primordial Follicle

Each primary oocyte in an egg nest is surrounded by follicle cells. Primary oocyte and follicle cells form a primordial follicle

Uterus

Encloses and supports developing embryo. uterus is a thick-walled, muscular, pear-shaped organ, which lies just above the urinary bladder.

Parasympathetic activation leads to

Engorgement of erectile tissues, Increased secretion of cervical mucous glands and greater vestibular glands

Uterine Tube and Fertilization

For fertilization to occur:Secondary oocyte must meet spermatozoa during first 12-24 hours Fertilization typically occurs:Near boundary between ampulla and isthmus. Uterine tube provides nutrient-rich environment by secretions from peg cells. Containing lipids and glycogen nutrients supply spermatozoa and developing pre-embryo

myometrium

Has a thick, outer, muscular. The thickest portion of the uterine wall constitutes almost 90 percent of the mass of the uterus. Arranged into longitudinal, circular, and oblique layers. Provides force to move fetus out of uterus into vagina

endometrium

Has a thin, inner, glandula. Contributes about 10 percent of uterine mass. Glandular and vascular tissues support physiological demands of growing fetus

Innervation of the Vagina

Hypogastric plexus, Sacral nerves, Branches of pudendal nerve

Three Segments of the Uterine Tubes

Infundibulum, Ampulla, Isthmus

Uterine Tube and Oocyte Transport

Involves ciliary movement and peristaltic contractions in walls of uterine tube. A few hours before ovulation, nerves from hypogastric plexus: "Turn on"beating pattern. Initiate peristalsis from infundibulum to uterine cavity. Normally takes three to four days

Uterine Cycle (Menstrual Cycle)

Is a repeating series of changes in endometrium lasts from 21 to 35 days. Average 28 days. Responds to hormones of ovarian cycle. The ovarian cycle is divided into the follicular phase, ovulation, and the luteal phase.

Hymen

Is an elastic epithelial fold that partially blocks entrance to vagina usually ruptured by sexual intercourse or tampon usage

perimetrium

Is an incomplete serous membrane. Continuous with peritoneal lining covers fundus and posterior surface of uterine body and isthmus

Vaginal Epithelium

Is nonkeratinized, stratified, and squamous. Forms folds (rugae). Changes with ovarian cycle

Menses

Is the degeneration of functional zone occurs in patches. Is caused by constriction of spiral arteries reducing blood flow, oxygen, and nutrients. Weakened arterial walls rupture releasing blood into connective tissues of functional zone

Menstruation

Is the process of endometrial sloughing lasts one to seven days Sheds 35-50 mL (1.2-1.7 oz) blood

Vaginal Lamina Propria

Is thick and elastic contains small blood vessels, nerves, and lymph nodes

colostrum

It takes a couple of days after delivery for milk production to begin, in the meantime, the breasts produce a watery, yellowish fluid called this. which differs from milk in that it contains more protein and less fat. good source of passive immunity for the baby.

Vestibular bulbs

Masses of erectile tissue that lie beneath the muscles. Have same embryological origins as corpus spongiosum of penis

corpus luteum

Once a follicle has lost its egg, it develops into this. If pregnancy does not occur, the corpus luteum degenerates. If pregnancy does occur, the corpus luteum persists, and secretes the female sex hormones estrogen and progesterone.

Process of Oogenesis

Primary oocytes remain in suspended development until puberty at puberty: Rising FSH triggers start of ovarian cycle Each month thereafter: Some primary oocytes are stimulated to develop further

The Female Reproductive System

Produces sex hormones and functional gametes Protects and supports developing embryo Nourishes newborn infan

Adolescence

Puberty. Burst of hormones activate maturation of the gonads: ovaries. Begins: 8-13 yrs of age abnormally early = precocious puberty Delayed =Primary Amenorrhea

Ovaries or female gonads

Release one immature gamete (oocyte) per month produce hormones

duct

Several secondary tubules come together to form a lactiferous

mesovarium

Stabilizes position of each ovary

Menopause

The termination of uterine cycles age 45-55. is the cessation of the menstrual cycle. after a woman reaches 20, the ovaries start to become progressively less responsive to gonadotropins. Estrogen & progesterone production therefore decreases throughout most of the woman's life finally the ovaries no longer secrete estrogen or progesterone. menstrual periods become irregular and eventually cease altogether. accompanied by hot flashes, headaches, nervous irritability, dizziness, depression, insomnia, etc. which are due to the reduction of estrogen levels.

alveoli,

Within each lobule are many small ________. which contain the secretory cells.

PCOS

affects about 8-10% of women. Very common. Do not release an egg (ovulate) regularly. Have ovaries that contain many small cystic structures, about 2-9 mm in diameter. complications of fertility

The luteal phase

after ovulation, LH causes the ruptured follicle to develop into a corpus luteum which secretes progesterone.

The Mammary Glands

breasts, contain 15-25 lobules. No milk is produced during pregnancy. During pregnancy, estrogen and progesterone inhibit the action of prolactin (lactogenic hormone). After birth, prolactin stimulates production of milk in the absence of these hormones. Sucking by the infant stimulates nerve endings in the nipples, which stimulates the hypothalamus, which: 1) releases prolactin, and 2) releases oxytocin which stimulates the release of milk from the lobules so that it flows into the ducts.

lactiferous ducts

carry the milk from the ampullae to the nipple.

body

central portion of uterus

Suspensory ligament

extends from ovary to pelvic wall - stabalize. Contains the ovarian artery and ovarian vein these vessels connect to ovary at ovarian hilum, where ovary attaches to mesovarium

Ovarian ligament

extends from uterus to ovary - holds in place

clitoris

form a hood. over a small knot of tissue erectile organ. homologous to the penis" and has sense receptors that allow it to function as a sexually sensitive organ.

The Uterine Cycle - Days 6-13

increased production of estrogen by an ovarian follicle causes the endometrium to thicken and to become vascular and glandular. This is called the proliferative phase of the uterine cycle. Ovulation usually occurs on the fourteenth day of the 28- day cycle

The Uterine Cycle - Days 15-28

increased production of progesterone by the corpus luteum causes the endometrium to double in thickness and the uterine glands to mature, producing a thick mucoid secretion. This is called the secretory phase of the uterine cycle. The endometrium is now prepared to receive the developing embryo, but if pregnancy does not occur, the corpus luteum degenerates and the low level of sex hormones causes the uterine lining to break down.

Vaginal Smear

is a sample of epithelial cells shed at surface of vagina Used to estimate stage in ovarian and uterine cycles

Progesterone

is also responsible for breast & uterus development; development of the uterus; and preparation of the uterus for implantation.

The Uterine Cycle - Days 1-5

low level of female sex hormones in the body, causing the uterine lining to disintegrate and its blood vessels to rupture. Blood flow, known as the menses, passes out of the vagina during a period of menstruation, or the menstrual phase.

The Uterine Wall

myometrium, endometrium, perimetrium

vaginal branches

of internal iliac (uterine) arteries and veins

Labia majora or "greater lips"

part around the vagina containing two glands (Bartholin's glands) which helps lubrication during intercourse. Male Homolog = scrotum cover and protect the urinary and genital openings.

Follicular phase

preovulatory phase. FSH secreted by the anterior pituitary, causing an ovarian follicle to mature.

Ovariohysterectomy

removal of the ovaries in addition to the uterus.

Hysterectomy

removal of the uterus

female orgasm

rhythmic spasms of muscles surrounding the vagina, and increased uterine motility which helps transport sperm toward the fallopian tubes.

fundus

rounded superior portion of uterus

hypothalamus

secretes GnRH(gonadotropic-releasing hormone).

The Cervix

the lower portion or neck of the uterus. lined with mucus, the quality and quantity of which is governed by monthly fluctuations in the levels of the estrogen and progesterone. estrogen levels are low, the mucus tends to be thick and sparse, hindering sperm from reaching the fallopian tubes. But when an egg is ready for fertilization, estrogen levels are high, the mucus then becomes thin and slippery, offering a "friendly environment" to sperm cervical canal expands to roughly 50 times its normal width in order to accommodate the passage of the baby during birth

estrogen and progesterone

which secrete the sex hormones. from ovaries

anterior pituitary

which secretes FSH (follicle stimulating hormone), LH (luteinizing hormone), which are the gonadotropic hormones

Luteal phase

(postovulatory phase)

Ampulla

Middle segment. smooth muscle layers in wall become thicker approaching uterus

Uterine glands

Open onto endometrial surface extend deep into lamina propria

Structural Support

Ovaries, uterine tubes, and uterus are enclosed in broad ligament. Uterine tubes-Run along broad ligament. Open into pelvic cavity lateral to ovaries

Three Functions of the Vagina

Passageway for elimination of menstrual fluids. Receives spermatozoa during sexual intercourse. forms inferior portion of birth canal

Amenorrhea

Primary amenorrhea failure to initiate menses transient secondary amenorrhea interruption of six months or more caused by physical or emotional stressed

vulva

The External Genitals collectively known as

The Duct System

The egg passes through the fallopian tube due to cilia and muscular contraction toward the uterus. If sperm are present in the fallopian tube, the egg maybe fertilized. The zygote may implant itself in the fallopian tube,which is also no good, and is also called an ectopic pregnancy. Fertilization normally occurs in the fallopian tube within twenty-four hours after ovulation.

Menarche

The first uterine cycle begins at puberty (age 11-12)