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Sexual Anatomy. Female-External Female-Internal Male-External Male-Internal. Female internal sex organs. The internal sexual organs of the human female: Ovaries Fallopian T ubes Uterus V agina. Ovaries. Defined: Female gonads that produce ova and sex hormones
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Sexual Anatomy Female-External Female-Internal Male-External Male-Internal
Female internal sex organs • The internal sexual organs of the human female: • Ovaries • Fallopian Tubes • Uterus • Vagina
Ovaries • Defined: Female gonads that produce ova and sex hormones • Each female has two ovaries about the size, shape, and texture of an irregular unshelled almond and dull gray in color. • Located at the ends of the fallopian tubes on each side of the uterus. • Attached to the uterus by ovarian ligaments, a type of connective tissue.
Ovaries • Female Gonads (Ovaries) perform two major functions: • Production of the female sex hormones estrogen and progesterone. • Estrogen: Hormone responsible for typical female sex characteristics. • Progesterone: Hormone that prepares and maintains the uterus for pregnancy. • Production of mature ova(egg cells). At birth a female infant’s ovaries contain about 400,000 immature ova which is all the eggs she will ever have. • Far more eggs than she will ever need • During reproductive years only about four to five hundred ripened eggs will be released for possible fertilization
Ovaries • Ovarian follicles: Small sacs containing ova. • After maturing in the ovarian follicles, eggs are released (usually one at a time) during the process of ovulation.
Ovaries • Ovulation: Discharge of a mature ovum from the ovary. • Released egg is gently drawn from the surface of the ovary into the fallopian tubes which takes approximately 3 or 4 days which is the period in which a woman is fertile. • Fertile: Time when pregnancy may occur • Fertilize: Join male and female cells, sperm and ova, so that offspring develop • If the egg is not fertilized during this time, it is expelled during menstruation.
Fallopian Tubes • Defined:Ducts that connect the ovaries to the uterus. • The twin fallopian tubes (oviducts) are hollow, muscular tubes approximately 10 centimeters or 4 inches long. • Attached one on each side of the uterus. • Extend outward from the uterus toward, but not attached directly to, the ovaries. • Each funnel-shaped fallopian tube fans out into fingerlike extensions called fimbriae, which drape over the ovary.
Fallopian Tubes • Fimbriae: Fingerlike projections at the end of the fallopian tube nearest the ovary that capture the egg and deliver it into the tube. • Hairlike cilia on the fimbriae become active during ovulation, coaxing the egg from the ovary and propelling it down the length of the tube toward the uterus. • If sperm are present, the egg may be fertilized while in the upper portion of the fallopian tube. • If the fertilized egg does not proceed all the way to the uterus, tubal pregnancy may result.
Uterus • Defined: Hollow, muscular internal female organ in which the fertilized egg develops until birth. • The uterus (womb) is a hollow, muscular organ shaped like an upside-down pear in which a fertilized egg implants and develops into a fetus. • The uterus is suspended in the pelvic cavity by a number of flexible ligaments. • Usually the uterus is positioned so that the top slants forward toward the abdomen (antroverted), although in about 10% of women the uterus tips backward toward the spine (retroverted). • Retroverteduterus generally becomes antroverted spontaneously during the third month of pregnancy • If a woman has not given birth the uterus is about 3 inches long, 3 inches wide, and bout an inch thick near the top and weighs about 2 ounces.
Uterus • No organ undergoes the same kind of dramatic change in adulthood as the uterus: • It grows to 2 pounds by the end of pregnancy, independent of the weight of the fetus or placenta. • After pregnancy it shrinks back almost (but not quite) to its original size.
Uterus • The uterus is divided into three major parts: • Fundus: Uppermost part of the uterus • Uterine Body: Central region of the uterus in which the fetus may develop • Cervix: small, lower end of the uterus that protrudes into the vagina and opens slightly for the release of menstrual blood and even more so for the birth of a baby • Viewed through the vagina the cervix of a woman who has never been pregnant appears like a smooth, pink disk with a small hole called the Os. • Os:Opening in the middle of the cervix that leads to the interior of the uterus.
Uterus • Uterine wall is composed of three layers: • Endometrium: Tissue that lines the inside of the uterine walls which is richly supplied with blood vessels and glands. • It is the endometrial tissue that is expelled through the cervix an dvagina during menstruation. • Myometrium: Smooth muscle layer of the uterine wall that gives the uterus strength and flexibility and is the source of the contractions necessary for childbirth. • Perimetrium: Thin membrane covering the outside of the uterus.
vagina • Defined: The stretchable canal that extends from the external genital opening to the cervix. • Elastic, muscular tube that extends back and upward from the external vaginal opening to the cervix. Vagina has three major functions: • Receptacle for the penis during sexual intercourse. • Passageway for menstrual flow. • Birth canal through which a fetus becomes a baby during childbirth.
Vagina • Vagina is a 3-5 inch long passageway built of skin, muscle, and fibrous tissue that extends at a 45 degree angle from the labia to the cervix. • At rest the walls of the vagina lie against one another. • During sexual arousal, the cervix lifts upward and the vagina expands in length to receive the penis. • The width of the vagina is similarly flexible to accommodate many dimensions, from an incoming penis or tampon to an outgoing baby.
Vagina • The walls of the vagina consist of three layers: • Vaginal Mucosa: Mucous membrane that is similar to the inside of the mouth. The cells of the vaginal mucosa are the source of vaginal lubrication that facilitates the insertion of a penis into the vagina during intercourse. • Muscularis: Middle layer of the vaginal walls, is muscular and it is these muscles that contract during orgasm. • Fibrous Layer: connects the vagina to other pelvic structures. • Vaginal walls are richly supplied with blood vessels throughout, but the sensory nerve endings are concentrated in the lower third of the vagina nearest the vaginal entrance.
Breasts • Breasts consist of 15 or 20 clusters of mammary glands, each with a separate opening to the nipple, surrounded by fatty and fibrous tissue. • Nipple - where milk ducts open; at the tip of the breasts. • Areola - area surrounding the nipple.