Reproductive Systems

The “opposite sex” is not opposite at all… Not only do both sexes develop from very similar structures (a pair of sex glands and two genital tubes) but both men and women manufacture the hormones of the other sex. Hormones of one sex are often used to treat illness in the other sex.  Men with certain heart ailments are mediated with the female hormone estrogen. Both sexes have reproductive organs called genitals or genitalia, designed for the purpose of intercourse and conception.

Male Internal Anatomy

Testis Scrotum Cowper’s gland Epididymis Penis Urethra Vas deferens Urinary bladder

Male Reproductive System Seminal vesicle Prostate gland Cowper’s gland Front View Urinary bladder Vas deferens Urethra Penis Epididymis Testis

Circumcision Foreskin: Protects the glands of the penis Provides sensation Men who have been circumcised do not have this Benefits of Circumcision: Easier Hygiene Decreased risk of urinary tract infections. Decreased risk of sexually transmitted infections. Prevention of penile problems.

Average Male Timeline Infancy Erections begin Ages Secondary sex characteristics appear Ages Sperm produced in adult amounts (puberty) Late teens Peak sexual urges for boys Throughout life If good health is present, there is the sex urge and ability to father children.

Female Internal Anatomy

Side View Urinary bladder Cervix Fallopian tube Ovary Uterus Vagina Urethra Female Reproductive System

Front View Cervix Fallopian tube Ovary Uterus Vagina

Hymen Variations A thin membrane that surrounds the opening to the vagina. Hymens can come in different shapes. The most common hymen in young girls is shaped like a half moon. This shape allows menstrual blood to flow out of a girl’s vagina.

Menstrual Cycle Women usually produce only one mature egg cell each month during a process called the menstrual cycle. During the menstrual cycle, an ovary releases a mature egg. The egg travels to the uterus. If the egg is not fertilized, the uterine lining is shed and a new cycle begins.

Menstrual Cycle Days 1–4 The uterine lining is shed during menstruation. Days 5–13 An egg matures in one of the ovaries, and the uterine lining starts to thicken. Egg Maturing Egg Days 14–15 The ovary releases the mature egg during ovulation. Days 16–22 The egg travels through the fallopian tube to the uterus, and the uterine lining continues to thicken. Days 23–28 The unfertilized egg enters the uterus.

Menstrual Discomfort Cramps are caused by contractions of the uterus. Premenstrual syndrome, or PMS, is marked by nervous tension, mood swings, headaches, bloating, and irritability. The dramatic change in hormone levels that occurs before menstruation begins may cause PMS.

Toxic Shock Syndrome Toxic shock syndrome (TSS) is a serious but uncommon infection caused by either Staphylococcus aureus (often called staph) and Streptococcus pyogenes (often called strep) bacteria, with most cases related to staph bacteria. TSS was originally linked to the use of tampons because the earliest cases, in the late 1970s, were related to super- absorbent tampons. Research led to better tampons and better habits for using them, such as changing them often. The number of TSS cases dropped dramatically. Today about half of all TSS cases are linked to menstruation.

Average Female Timeline Ages 9-12 Secondary sex characteristics appear Ages Menstrual cycle begins Late 20-30’s Peak sexual urges Ages Menopause Occurs (cycle stops, but sex urge continues)