Bio 27: September 12, 2012

1. Bio 27: September 12, 2012 Chapter 3: Female Sexual Anatomy & Physiology Chapter 4: Male Sexual Anatomy & Physiology

2. chapter 3: female sexual anatomy and physiology

3. Gynecological Health Concerns • Hysterectomy (removal of the uterus) or oophorectomy (removal of the ovaries) • Used in cases of cancer of the cervix, uterus or ovaries • Hysterectomy is most frequently performed U.S. operation (33% of women undergo by age 65) • Also used to treat fibroids (non-cancerous growths), endometriosis, pelvic pain, and irregular bleeding • Hysterectomy may decrease sexual response in many women; oophorectomy induces the same hormonal changes associated with menopause unless replacement hormones are taken • More common in poor and less educated women

4. the breasts

5. Breasts • Breasts are a secondary sex characteristic: something other than genitals that distinguishes men and women • Mammary glands produce milk after pregnancy • Areola is darker area • Nipple is in center of areola & has openings for milk

6. Cross-Section of Breast

7. Breast Health Problems • Breast Lumps: can be detected by self exam • Cysts (fluid-filled sacs) • Fibroadenomas (solid, round, benign tumors) • Malignant tumor • Breast cancer • Treatments: surgery, chemotherapy, radiation • Risk factors: age, hormones, smoking, family history • Reconstructive breast surgery • Early detection & treatment boosts survival

8. Chapter 4 Male Sexual Anatomy and Physiology

9. Male genitalia are as diverse as female genitalia

10. The Penis • Consists of nerves, blood vessels, fibrous tissue & spongy tissue; no bones! • Interior portion of the penis is the root • Head of the penis is called the glans; this is surrounded by a ridge called the corona • Remainder of penis is the shaft

11. The Penis • Like the vagina, the penis has 3 layers of tissue: 2 cavernous bodies, and 1 spongy body • These fill with blood during sexual excitation, creating an erection

12. The foreskin & circumcision • The glans of the penis is covered by a loose layer of skin called the foreskin • Some cultures practice removal of the foreskin, usually in infant boys

13. Circumcision for health? • 1971: American Academy of Pediatrics states that there is no medical benefit to circumcision • 1989: AAP states that there are “potential benefits” • 1999: AAP states that there are “insufficient data” to recommend circumcision • 2012: AAP states that the health benefits of circumcision outweigh the risks

14. Circumcision: pros and cons Cons: • Complications can arise (rare) • Foreskin removal may cause trauma from pain • Reduced sexual enjoyment (?-controversial) • Cannot be easily reversed Pros: • Circumcision reduces rates of sexually transmitted diseases, including HIV • Also reduces risk of urinary tract and bladder infections, and of cancer For many parents, medical concerns are secondary to religious/cultural or appearance concerns

15. The scrotum • Scrotum: pouch with two chambers for each of two testicles or testes • Has two layers: • skin layer: skin is darker than on rest of body and becomes covered with hair at puberty; analogous to labia majora in women • tunica dartos: muscle layer • Pulls sac closer to body in cold temperatures

16. The scrotum and testes • Testes are the equivalent of the ovaries in females • Make sperm and also testosterone and other hormones • Spermatic cord holds each testis • Also contains the vas deferens, which delivers sperm from the testes to the penis (a vasectomy is surgical closing off of the vas deferens)

17. The testes • Male gonads (testes) are outside the body unlike female gonads (ovaries) • This is true for most but not all mammals • Sperm survive yet at a temp slightly cooler than body temperature

18. Castration • Castration: surgical removal of the testes; drastically decreases testosterone and male sexual behavior; destroys fertility • Eunuchs: men or boys who have undergone castration • Castration has been used as punishment; many cultures have castrated slaves or servants • Castration before puberty was used until the 19th century in Europe to preserve the singing voices of boys; some boys’ voices still underwent changes

19. The testes: function • Seminiferous tubules: site of sperm production • Sperm travel from there to the epididymis, where they are stored • Interstitial cells between seminiferous tubules make most of the body’s testosterone

20. Testicular problems: Cryptorchidism • In male fetuses, testes develop inside the abdominal cavity and usually descend into the scrotum by birth • Cryptorchidism: failure of the testes to descend; affects 3–5% of male infants • Can result in infertility and increased risk of cancer, but can be treated very effectively with hormones and/or surgery

21. Testicular problems: testicular cancer • Most common cancer in males age 20–35 • Accounts for 1–2% of all cancers in males • Risk factors include smoking, family history, white race, and cryptorchidism • Usually shows up as a mass in one testicle, can be detected by male genital self-exam (described in book) • Early detection results in greater than 90% survival

22. The prostate • The prostate makes seminal fluid, the fluid in which sperm leave the body • Seminal fluid + sperm = semen • 50% of men over age 60 and 90% of men over age 90 experience benign prostatic hyperplasia or an enlarged prostate • This can cause urinary issues!

23. Prostate cancer • Second most common cancer in American males (after skin cancer) • Risk factors are: old age, family history, high-fat diet, African-American race • 218,000 U.S. men are diagnosed each year and 28,000 U.S. men die from it each year • Can be detected with a blood test (somewhat controversial) or with a physical examination (digital rectal examination)

24. “Male and female reproductive anatomy shows more similarities than differences” How strongly do you agree or disagree with this statement? Support your answer with specific evidence.