Hot Stuff for the end of the semester, Fall 04 I Reproductive System A) Current issues related to the Reproductive System: Abortion, contraception, homosexuality, premature births, sperm and egg and embryo banks, drug abusing mothers, rape, menopause, infertility, in vitro fertilization, fertility pills, surrogate mothers, sex scandals (politicians, celebreties, other), etc.... B) Contraception - preventing pregnancy History of contraception Egyptians - honey, crocodile dung, fermented acacia extract as vaginal suppositories Romans and Greeks - lint tampon to block sperm, also used abortion to terminate pregnancy Europeans in Middle Ages - cedar oil, cabbage, pitch, ox-gall, elephant dung Europeans in the Renaissance - invention of the condom, vaginal sponge with brandy 1) Behavioral techniques
| Type | Technique | % effectiveness |
| Abstinence | no sex | 100% |
| Rhythm Method | Natural Family Planning, intercourse before ovulation or during menstruation | 76-90% |
| Coitus Interruptus or withdrawal | pulling the penis out of the vagina before ejaculation | 72-77% |
2) Barriers
| Type | Technique | % effectiveness |
| Diaphragm | barrier with spermicide | 82-94% |
| Condom | latex sheath placed over the penis | 88-99% |
| Vaginal tampons | structures used by ancient and medieval civilizations, may be accompanied by vinegar, hemlock, opium, honey which were used as spermicides | % effectiveness unknown |
3) Surgical sterilization
| Type | Technique | % effectiveness |
| Vasectomy - males | tie off vas deferens | 99.9% |
| Tubal ligation- females | tie off Fallopian tubes | 99.9% |
| Sterilization | removal of gonads | 100% |
4) Chemical
| Type | Technique | % effectiveness |
| Douche with spermicide | spermicide | 70-85% |
| Oral contraception | the pill, suppresses ovulation by releasing estrogen and progesterone derivatives, inhibits release of FSH and LH | 95%-98% |
| Implants | similar to pill, but it is am implant under the skin which gradually releases progesterone derivatives | nearly 100% |
| Injections - Depo-Provera | injection that lasts up to 3 months | 99% |
| Lunelle | injection that lasts up to 1 month | 99% |
5) Irritant - IUD - probably acts as an irritant to prevent implantation, 95-99% effective, controversial because of many harmful side-effects reported 6) Various web sites with comparisons of effectiveness of contraceptive techniques East Tennessee State University Oklahoma State University Southern Illinois University - nice overview C) Abortion (termination of a pregnancy) - defintions and methods a) Early in pregnancy (before 14 weeks) Vacuum aspiration - suction (6-9 weeks) D&C (dilation and curettage) - scraping the walls of the uterus (8-16 weeks) RU 486 - competes for progesterone receptors, disrupts communication between embryo (secretes HCG) and corpus luteum (5-7 weeks) MAP (Morning After Pill Links) - also known as emergency contraception (90-95% effective at preventing pregnancy), pill is made up of large doses of synthetic hormones found in the birth control pill, estrogen alone, progesterone alone or estrogen and progesterone together (taken within 72 hours of intercourse) M&M - methotrexate interferes with mitosis, used with misoprostol (95% effective, taken 5-9 weeks) b) Later in pregnancy (after 14 weeks) D&E (dilation and evacuation) - fetus is surgically destroyed and removed (13-20+ weeks) D&X (dilation and destruction) destruction of the brain followed by removal referred to as the partial birth abortion (20-32+ weeks) D) Female Genitalia - External a) labia - equivalent to scrotum of male b) clitoris - equivalent of the male penis, swells during sexual arousal E) Female Genitalia - Internal 1) Ovary - contains the eggs, site of beginning of meiosis - egg production a) females born with all the eggs they will use in a lifetime, oocytes develop within follicles in the ovary b) meiosis I produces secondary oocyte contained in follicle (follicle development) c) ovulation - release of secondary oocyte where meiosis is arrested, meiosis II begins only after stimulation by sperm during fertilization 2) Fallopian tubes - catches eggs released from ovary during ovulation a) where most fertilizations occur 3) Uterus - area of implantation of fertilized egg(s) a) lining is the endometrium, thickens during the end of female cycle in anticipation of implantation 4) Cervix - entry into the uterus from the vagina 5) Vagina - copulatory organ of females, receives penis and sperm after ejaculation 6) Hormonal control and the menstrual cycle and follicle development Ant. pituitary produces LH and FSH - stimulates development surge in LH and FSH cause ovuation - release of the egg/ovum from follicle ruptured follicle becomes the Corpus Lutem Corpus luteum secretes progesterone and estrogen to maintain lining F) Male - External genitalia 1) Scrotum (scrotal sac) - houses testes outside the body) 2) Testes, enclosed in scrotum outside of body, site of sperm production a) seminiferous tubules - where meiosis takes place b) 100 - 650 million sperm/ejaculation c) sperm structure - head (acrosome and nucleus), middle (mitochondrion) tail = flagellum 3) Penis, copulatory organ, spongy erectile tissue, blood vessels a) Urethra - tube inside the penis that carries sperm and urine G) Male - Internal genitalia 1) Ductus (Vas) deferens - connect testes to penis, squeeze sperm forward during ejaculation 2) Seminal Vesicles - secrete sugars for sperm (energy) 3) Prostate Gland - secretes alkaline liquid which neutralizes acidic environment in the vagina, stimulates activity of sperm 4) Bulbourethral gland - secretes mucus for motility 5) Semen - sperm + other chemicals mentioned above II Fertilization, Development and Diseases A) Human Copulation 1) 4 Phases Excitement Plateau Orgasm Resolution B) Coitus and fertilization 1) Internal fertilization sexual arousal (penis in males and breasts, females - breast, labia, clitoris) coitus leads to orgasm, ejaculation in males sperm swims to egg in oviduct and fertilization begins, sperm contacts the egg and membranes fuse, exocytosis by the sperm releases its contents into the egg (acrosomal reaction), causes depolarization of the egg cell membrane = fast block to polyspermy C) Development 1) zygotes undergoes mitosis 1 day after fertilization 2) mass of cells becomes a blastocyst 5 days after fertilization 3) implanation of blastocyst about 7 days after fertilization 4) formation of the placenta (cells from embryo and mother) 5) blastocyst produces HCG which stimulates corpus luteum to produce estrogen and progesterone 6) Trimesters - result in growth, differentiation and morphogenisis 1st Trimeseter - embryo grows, after 7 weeks becomes fetus mass of cells transforms into fetus with some working parts (e.g., kidneys), bone deposition, blood formation, external sex ograns develop 2nd Trimeseter - significant increase in size, some reflexes and movement (e.g., thumbsucking and gripping) 3rd Trimeseter - growth accelerates, baby becomes fatter, prepared for living independently D) Birth/Parturition Uterus begins powerful, rhythmic contractions - labor Initiated by increasing concentrations of estrogen, decreasing amounts of progesterone towards end of pregnancy oxytocin released by post. pituitary during labor D) Lactation Estrogen, Progesterone prepare breasts PRL stimulates maturity of the breasts and milk production PRL levels increase after parturition Oxytocin is released by tactile stimulation of the infant nursing on the breasts E) Sexually Transmitted Diseases (STDs) 1) Herpes simplex II - viruses cause 2 types (oral and genital) 2) Trichonomonas - protozoan causes burning and vaginal discharge 3) Chlamydia - bacterium causes painful urination, can lead to arthritis, heart disease, and other symptoms in men 4) Syphillis - bacterium, 3 stages (sores followed by rash followed by invasion of the organ systems 5) Gonorrhea - bacterium causes inflammation of reproductive tract, pelvis (PID), can spread to other parts of the body (heart, joints) 6) AIDS - see Immune system
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