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Female Reproductive System

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Presentation on theme: "Female Reproductive System"— Presentation transcript:

1 Female Reproductive System

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

3 Function of Female Reproductive System
Produce sex hormones Produce functioning gamates [ova] Support & protect developing embryo

4 General Physical Changes
Axillary & pubic hair growth Changes in body conformation [widening of hips, development of breasts] Onset of first menstrual period [menarche] Mental changes

5 Major Organs Ovaries [ gonads] Uterine tubes [ fallopian tubes] Uterus
Vagina Accessory glands External genitalia Breasts

6 month in fertile women.                                                 . ovaries Each ovary is about the size and shape of an almond. After menopause they tend to shrink. they produce eggs (also called ova) every female is born with a lifetime supply of eggs they also produce hormones: Estrogen  & Progesterone Male Homolog = testes They are among the first organs to be formed as a female baby develops in the uterus. At the 20-week mark, the structures that will become the ovaries house roughly 6 to 7 million potential egg cells. From that point on, the number begins to decrease rapidly. A newborn infant has between 1 million to 2 million egg cells. By puberty the number has plummeted to 300,000. For every egg that matures and undergoes ovulation, roughly a thousand will fail, so that by menopause, only a few thousand remain. During the course of an average reproductive lifespan, roughly 300 mature eggs are produced for potential conception. The ovaries produce these hormones throughout the fertile period of a woman's life. It is the hormones that control the menstrual cycle. As you get older and menopause approaches, the ovaries make less and less of these hormones and the periods eventually stop altogether. So the normal ovaries cannot usually be felt in a clinical examination except in young, thin women. The ovaries are the main source of female hormones (estrogen and progesterone). These hormones control the development of female body characteristics, such as the breasts, body shape, and body hair. They also regulate the menstrual cycle and pregnancy. What is estrogen? Estrogen is a group of female sex hormones that stimulate the appearance of secondary female sex characteristics in girls at puberty. Estrogen controls controls the growth of the lining of the uterus during the first part of the menstrual cycle, cause breast development in pregnancy and regulates various metabolic processes.

7 fallopian tubes [uterine tubes]
stretch from the uterus to the ovaries and measure about 8 to 13 cm in length. range in width from about one inch at the end next to the ovary, to the diameter of a strand of thin spaghetti. The ends of the fallopian tubes lying next to the ovaries feather into ends called fimbria Millions of tiny hair-like cilia line the fimbria and interior of the fallopian tubes. The cilia beat in waves hundreds of times a second catching the egg at ovulation and moving it through the tube to the uterine cavity. Fertilization typically occurs in the fallopian tube (4 to 6 inches) = length called fimbria (Latin for "fringes" or "fingers").each tube has about about 20 to 25 Millions of tiny hair-like cilia line the fimbria and interior of the fallopian tubes. The cilia beat in waves hundreds of times a second catching the egg at ovulation and moving it through the tube to the uterine cavity. Other cells in the tube's inner lining or endothelium nourish the egg and lubricate it's path during its stay inside the fallopian tube. Once inside the fallopian tube, the egg and sperm meet and the egg is fertilized. If an egg doesn't become fertilized within 24 to 36 hours after ovulation, it will deteriorate and be removed by the body's immune system like any other dead cell in the body.

8 uterus pear-shaped muscular organ in the upper female reproductive tract. The fundus is the upper portion of the uterus where pregnancy occurs. The cervix is the lower portion of the uterus that connects with the vagina and serves as a sphincter to keep the uterus closed during pregnancy until it is time to deliver a baby. the uterus expands considerably during the reproductive process…10 to 20 times its normal size during pregnancy. Size = 3 in long x2 inch diameter Weighs about oz Pregnancy – watermelon sized 

9 uterus The main body consists of a firm outer coat of muscle (myometrium) and an inner lining of vascular, glandular material (endometrium). The endometrium thickens during the menstrual cycle to allow implantation of a fertilized egg. Pregnancy occurs when the fertilized egg implants successfully into the endometrial lining. If fertilization does not occur, the endometrium sloughs off and is expelled as menstrual flow. Endometrium is about 10% of uterus mass – myometrium almost 90% - thin outer coat called perimetrium This cyclic process – the menstrual cycle – results from the interaction between the female reproductive organs and the endocrine system.

10 Each month the uterus goes through a cyclical change, first building up its endometrium or inner lining to receive a fertilized egg, then, if conception does not occur, shedding the unused tissue through the vagina in the monthly process called menstruation

11 The Cervix the lower portion or neck of the uterus.
The cervix is lined with mucus, the quality and quantity of which is governed by monthly fluctuations in the levels of the estrogen and progesterone. When 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 at the end of pregnancy, the cervix acts as the passage through which the baby exits the uterus into the vagina. The cervical canal expands to roughly 50 times its normal width in order to accommodate the passage of the baby during birth The vagina ends at the cervix, (cervical mucus changes: employed by birth control pills, shots and implants. One of the ways they prevent conception is to render the cervical mucus thick, sparse, and hostile to sperm.)

12 The Vagina vagin = sheath
a muscular, ridged sheath connecting the external genitals to the uterus. functions as a two-way street, accepting the penis and sperm during intercourse and roughly nine months later, serving as the avenue of birth through which the new baby enters the world

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14 External genetalia vulva—which runs from the pubic area downward to the rectum. Mons pubis or "mound of Venus" is the V-shaped area covered with hair Labia majora or "greater lips" are the part around the vagina containing two glands (Bartholin’s glands)which helps lubrication during intercourse. Male Homolog = scrotum Labia minora or "lesser lips" are the thin hairless ridges at the entrance of the vagina, which joins behind and in front. In front they split to enclose the clitoris The clitoris is a small pea-shaped structure (equivalent to penis in males ) It plays an important part in sexual excitement in females. Male Homolog = penis

15 External genetalia The urethral orifice or external urinary opening is below the clitoris on the upper wall of the vagina and is the passage for urine The introitus or opening of the vagina is separate from the urinary opening (unlike males) and located below it. The hymen is a thin cresentic fold of tissue which partially covers the opening of the vagina. medically it is no longer considered to be a 100% proof of female virginity. It was thought to be proof of virginity as it is broken after the first sexual intercourse. However it is stretchable, and may break due to vigorous exercises, cycling, gymnastics or tampon use.Therefore

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17 Mammary Glands [ breasts]
Present in both sexes - normally only functional in females Developmentally they are derived from sweat glands Contained within a rounded skin-covered breast anterior to the pectoral muscles of the thorax Slightly below center of each breast is a ring of pigmented skin, the areola - this surrounds a central protruding nipple Internally - they consist of 15 to 25 lobes that radiate around and open at the nipple Each lobe is composed of smaller lobules- these contain alveoli that produce milk when a women is lactating non-pregnant women - glandular structure is undeveloped - hence breast size is largely due to the amount of fat deposits Large sebaceous glands in the areola make it slightly bumpy & produce sebum that reduces chapping and cracking of the skin of the nipple Autonomic NS controls smooth muscle fibers in the areola and nipple cause the nipple to become erect when stimulated by tactile or sexual stimuli & when exposed to the cold Lobes are padded & separated from each other by fibrous connective tissue and fat The connective tissue forms suspensory ligaments that attach the breast to the underlying muscle fascia

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19 glands Lesser Vestibular (Paraurethral, Skene's) Male Homolog = prostate located on the upper wall of the vagina, around the lower end of the urethra. They drain into the urethra and near the urethral opening Function - mucus production to aid lubrication during intercourse Greater Vestibular (Bartholin's) Male Homolog = bulbourethral glands located slightly below and to the left and right of the opening of the vagina. They secrete mucus to provide lubrication, especially when the woman is sexually aroused

20 Hormones and the menstrual cycle
The female hormones that control the cyclic growth and shedding of the endometrium are estrogen and progesterone. Estrogen and progesterone are produced by the ovaries. Estrogen causes the growth or proliferation of the endometrium during the first 2 weeks of the menstrual cycle. After ovulation, the ovary produces progesterone. Progesterone causes the endometrial glands to secrete nutritive substances required by the embryo and to allow it to implant into the endometrial lining. If fertilization and implantation do not occur, the progesterone falls and the endometrial lining is sloughed off - resulting in menstrual bleeding. If fertilization and implantation do occur, then the ovary continues producing progesterone and the endometrium remains intact to support embryo development and pregnancy. After ovulation, in the space where the egg used to be, a second small cystic area known as the corpus luteum develops and begins to secrete progesterone. The corpus luteum eventually gets reabsorbed by the ovary.

21 When does ovulation occur?
The timing of ovulation varies with the length of a woman's menstrual cycle. In the average 28 day menstrual cycle, the LH surge usually occurs between cycle days and ovulation follows about hours later, on or close to cycle day 14. Women with shorter menstrual cycle lengths tend to ovulate earlier and women with longer cycle lengths tend to ovulate later than cycle day 14. Despite the variations in menstrual cycle length, the time from ovulation to the onset of the next menstrual period is usually constant (2 weeks). This principle is the basis for the use of ovulation calendars that take into account an individual's shortest and longest cycle lengths. (It is the mid-cycle surge of the hormone LH that causes the dominant follicle to rupture and release the mature egg.)

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