REPRODUCTIVE SYSTEM

• The reproductive system is a complex network of organs and tissues that work together to facilitate the process of sexual reproduction.
• The mammary glands synthesize, secrete, and eject milk for nourishment of the newborn.
• The uterus is the site of implantation of a fertilized ovum, development of the fetus during pregnancy, and labor.
• The vagina receives the penis during sexual intercourse and is a passageway for childbirth.
• The male and female reproductive organs can be grouped by function.
• The gonads, testes in males and ovaries in females, produce gametes and secrete sex hormones.
• Supporting structures, such as the penis in males and the uterus in females, assist the delivery of gametes, and the uterus is also the site for the growth of the embryo and fetus during pregnancy.
• The organs of the male reproductive system include the testes, a system of ducts (epididymis, ductus deferens, ejaculatory ducts, and urethra), accessory sex glands (seminal vesicles, prostate, and bulbourethral glands), scrotum, penis, and cremaster muscle.
• The testes produce sperm and the male sex hormone testosterone.
• Surgical sterilization is an intervention to render an individual incapable of reproduction.
• Barrier methods employ a physical barrier to block sperm from gaining access to the uterine cavity and tubes.
• Tubal ligation is a surgical method used in females to tie closed and then cut the uterine (fallopian) tubes.
• The high levels of estrogens during the last part of the preovulatory phase have a positive feedback effect on cells secreting LH and GnRH, thus bringing about ovulation.
• Birth control methods are designed to limit the number of children produced by preventing conception.
• Vasectomy is a surgical method used in males by removing a portion of the vas deferens.
• There are several types of oral hormonal methods of contraception: Combined oral contraceptives (COC) contain progestin and estrogens, Extended cycle birth control pills contain progestin and estrogen, and menstruation occurs every 13 weeks, Minipills contain progestin only, and Progestin thickens cervical mucous.
• Contraceptive skin patch and Vaginal contraceptive ring are other methods of birth control.
• Hormonal methods of birth control include oral contraceptives that are designed to prevent pregnancy by inhibiting ovulation.
• Feedback is important in regulating hormonally controlled cycles.
• There are many hormonal interactions between the ovarian and uterine cycles.
• Other methods of birth control include surgical sterilization, hormonal methods, and periodic abstinence.
• Emergency contraception (EC) includes an oral method where two pills are taken, one within 72 hours of unprotected intercourse and the other is taken 12 hours after the first.
• Non-incisional sterilization employs the insertion of a coil made of plastic and metal into each uterine tube, then scar tissue grows and blocks the tubes.
• Complete abstinence is the only 100% reliable method of birth control.
• The ducts transport, store, and assist in maturation of sperm.
• The accessory sex glands secrete most of the liquid portion of semen.
• The penis contains the urethra, a passageway for ejaculation of semen and excretion of urine.
• The scrotum is a sac of loose skin and underlying subcutaneous tissue that contains the testes, internally separated into two compartments by the scrotal septum.
• The cremaster muscle is a series of small bands of skeletal muscle that descend through the spermatic cord to surround the testes, made up of subcutaneous layer and muscle tissue.
• The testes are paired, oval glands in the scrotum partially covered by the tunica vaginalis, internal to the tunica vaginalis is a connective tissue capsule, the tunica albuginea that extends inward to form septa that create compartments.
• Seminiferous tubules carry sperm produced within them (spermatogenesis) out of the testes, 5 cm (2 in.) long and 2.5 cm (1 in.) in diameter, each testis has a mass of 10-15 grams.
• These branch into radial arteries that go deep into the myometrium.
• Mammary glands are located in each of the two breasts and are modified sudoriferous glands that produce milk, containing 15–30 lobes with lobules containing milk secreting glands called alveoli, and each breast has a nipple containing lactiferous ducts where milk emerges.
• Uterine arteries give rise to arcuate arteries that feed the myometrium.
• The ovarian cycle includes changes that occur during and after maturation of the oocyte.
• Greater vestibular (Bartholin’s) glands produce mucous during sexual arousal to provide lubrication, and are homologous to the bulbourethral gland.
• The vulva (pudendum) refers to the external genitalia of the female, including the mons pubis, labia minora, labia majora, clitoris, and vestibule (hymen, vaginal orifice, external urethral orifice, openings of ducts of several glands).
• The stratum basalis layer is permanent and gives rise to a new stratum functionalis after each menstruation.
• The muscularis is composed of an outer circular layer and inner longitudinal layer of smooth muscle, allowing the vagina to stretch during intercourse and childbirth.
• The vagina is a fibromuscular canal lined with mucous that extends from the body’s exterior to the cervix.