OBJECTIVES FOR TODAY ANATOMY/ RESPONSE CYCLE & HEALTH ISSUES
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Q and A U of A Survey Embryonic Development brief Female Sexual Anatomy Male Sexual Anatomy Sexual Response Cycle Health Issues

ANATOMY & PHYSIOLOGY

Embryonic Development
CHROMOSOMES 23 from males, 23 from female - form 23 pairs. Ovum has X chromosomes sperm has X or Y chromosomes XX - female embryo XY - male embryo 5-6 wks primitive gonads, ducts, external genital 7 wks begins to differentiate to male/female Basic blueprint female - some become male

Embryonic Development (cont.)
HORMONES: Androgens, especially testosterone, produced in testes influence male development Lack of androgens leads to female development (Female hormones important in puberty)
Testes & Ovaries begin high in abdomen - ovaries descend to pelvis, testes to scrotal sac. Undescended testes may correct in early life - if not, moved surgically. (Risk of cancer & sterility) A variety of developmental anomalies. Early decisions re: gender assignment vital.

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At 18 months, the appearance is female though undescended testes are present.

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Age 4 Lacking dihydrotestosterone (DHT) in utero, this boy's external genitalia develop as female. However, internally the gonadal tissue is that of normal male and his karyotype is 46 XY (normal male).

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Age 8 In utero, DHT is essential for the normal male development of the external genitalia. After complete maturation, DHT seems to have no important biological function.

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Age 12 Just before puberty, prior to the testosterone outpouring, the phenotype is still female.

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Age 19 With the testosterone surge at puberty, the phenotype changes to male: the voice deepens, the testes descend, the phallus grows, erection and ejaculation begin, and a male psychosexual orientation develops.

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Age 42 for the rest of their lives, the guevedoces resemble the other Dominican men in all respects except: * Beard growth is scanty. * There is no hairline recession. * None has acne. * The prostate remains small.

Anatomy
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Female Organs
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Male Organs
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Glans of clitoris Shaft of clitoris Hood of clitoris Labia majora Labia minora Skene’s glands Bartholin’s glands Ovaries

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Glans of penis Shaft of penis Foreskin of Penis Scrotal sac Underside of penile shaft Prostate gland Cowper’s glands Testes

Female Sexual Anatomy and Physiology
Mons Veneris  fatty tissue that covers the joint of the pubic bones in front of the body, below the abdomen and above the clitoris. Function: Mons cushions a woman=s body during intercourse. Labia Majora  Large folds of skin that run downward from the mons along the sides of the vulva. Function: amply supplied with nerve endings that respond to stimulation. They also shield the inner portions of the female genitals.

Female Sexual Anatomy and Physiology (continued)
Labia Minora  2 hairless, light coloured membranes located between the major lips. They surround the urethral and vaginal opening. At the top they join at the prepuce (hood) of the clitoris. Function: Rich in blood vessels and nerve endings, the labia minora are highly sensitive to sexual stimulation. When stimulated they darken and swell.
Clitoris  a female sex organ consisting of a shaft and glans located above the urethra opening. Function: unique in that it serves no known purpose other than sexual pleasure.

Female Sexual Anatomy and Physiology (continued)
Prepuce of clitoris  “hood” cover the clitoral shaft Urethral opening  opening through which urine passes from the female’s body Vaginal opening  also called introitus. Hymen is a fold of tissue across the vaginal opening is usually present at birth and remains at least partially intact until the women engages in intercourse.

Female Sexual Anatomy and Physiology (continued)
Pubo coccygeus muscle  the muscles that encircle the entrance to the vagina.

Kegel