BIOH 370 1st editionLecture 35 Outline of Last Lecture Reproductive System Day 4I. The VaginaII. External Genitalia (Vulva or Pudendum)III. The Ovarian CycleIV. Effects of Estrogen and ProgesteroneV. Failure Rates for Birth Control MethodsVI. Mammary GlandsVII. Breast CancerVIII. Female Sexual ResponseIX. STIsa. Gonorrheab. Syphilisc. ChlamydiaOutline of Current Lecture Reproductive System Day 5 & Development and InheritanceI. STIs:a. Bacteriali. Gonorrheaii. SyphilisThese notes represent a detailed interpretation of the professor’s lecture. GradeBuddy is best used as a supplement to your own notes, not as a substitute.iii. Chlamydiab. Virali. Genital Wartsii. Genital HerpesII. Reproductive System Developmental Aspects- Sex DeterminationIII. Male/Female Homologous Reproductive OrgansIV. MenopauseV. Development and Inheritancea. From Egg to Zygoteb. Fertilizationc. Embryonic Developmentd. Formation of PlacentaVI. Changes During Pregnancya. Maternal Changesb. Hormonal ChangesVII. Embryonic PeriodCurrent LectureReproductive System Day 5 & Development and InheritanceI. STIs:a. Bacteriali. Gonorrhea- Bacterial infection of mucosae of reproductive and urinary tracts- Spread by contact with genital, anal, and pharyngeal mucosae - Signs and symptoms- Maleso Urethritis, painful urination, discharge of pus - Femaleso 20% display no signs or symptomso Abdominal discomfort, vaginal discharge, or abnormal uterine bleedingo Can result in pelvic inflammatory disease and sterility- Treatment: antibiotics, but resistant strains are becoming prevalentii. Syphilis:- Bacterial infection transmitted sexually or contracted congenitallyo Infected fetuses are stillborn or die shortly after birth- Infection is asymptomatic for 2–3 weeks- A painless chancre appears at the site of infection and disappears in a few weeks- If untreated, secondary signs appear several weeks later for 3–12 weeks,and then disappear: pink skin rash, fever, and joint pain- The latent period may or may not progress to tertiary syphilis, characterized by gummas (lesions of the CNS, blood vessels, bones, and skin)- Treatment: penicilliniii. Chlamydia:- Most common bacterial STI in the United States- Responsible for 25–50% of all diagnosed cases of pelvic inflammatory disease- Symptoms: urethritis; penile and vaginal discharges; abdominal, rectal, or testicular pain; painful intercourse; irregular menses- Can cause arthritis and urinary tract infections in men, and sterility in women- Treatment: tetracyclineb. Virali. Genital Warts:- Caused by human papillomavirus (HPV)- Second most common STI in the United States- Increase the risk of cancers in infected body regions- Two vaccines (Cervarix and Gardasil) are available to protect females against the types of HPV that cause most cervical cancers. One of these vaccines - (Gardasil) also protects against most genital warts. Both vaccines are recommended for 11 and 12 year-old girls, and for females 13 through 26 years old, who did not get any or all of the three recommended doses when they were younger. These vaccines can also be given to girls beginning at age 9. It is recommended that females get the same vaccine brand for all three doses, whenever possible. - One available vaccine (Gardasil) protects males against most genital warts. This vaccine is available for boys and men, 9 through 26 years of age. ii. Genital Herpes:- Caused by human herpes virus type 2- Characterized by latent periods and flare-ups- Congenital herpes can cause malformations of a fetus- Treatment: acyclovir and other antiviral drugsII. Reproductive System Developmental Aspects- About two months before birth- Testosterone stimulates the migration of the testes toward the scrotum- Ovaries also descend, but are stopped by the broad ligament at the pelvic brim- Gubernaculum: fibrous cord from each testis to the scrotum or from ovary to labium majus; guides the descent- The first decade: reproductive system in juvenile state- Age 10: hormone-directed changes leading to puberty- Puberty: males begin to produce sperm, females enter menarche (beginning of menstruation). - With age, fertility declines. Between 30–40, ovarian follicles become exhausted. Estrogen levels decline.- In males, reproduction is still possible into the eighties or nineties. - At around age 55, testosterone levels decline, sperm levels drop, sexual desire wanes.- Most males over 60 experience benign prostatic hypertrophy where theprostate enlarges to two to four times its normal size.- Sex Determination:o Sexually indifferent stageo Gonads begin development in fifth week as gonadal ridgeso Paramesonephric (Müllerian) ducts (future female ducts) form lateral to the mesonephric (Wolffian) ducts (future male ducts)o Primordial germ cells migrate to the gonadal ridges to provide germ cells destined to become spermatogonia or oogoniao Gonads begin development in seventh week in males, eighth week in females- SRY: Sex-determining Region of the Y chromosome controls the secretion of Mullerian-inhibiting Substance (MIS)- Males Testes produce MIS = inhibit female developmentTestes produce androgens = enhance male development- Females Ovaries do not produce MIS = enhance female developmentOvaries do not produce androgens = inhibit male developmentOvaries 8- to 9-week female fetus Paramesonephric duct forming the uterine tube Mesonephric duct (degenerating) Fused paramesonephric ducts forming the uterus Urinary bladder (moved aside) Urogenital sinus forming the urethra and lower vagina Paramesonephric duct (degenerating) Testes Mesonephric duct forming the ductus deferens Urinary bladder Seminal vesicle Urogenital sinus forming the urethra Epididymis Efferent ductules 7- to 8-week male embryo III. Male/Female Homologous Reproductive Organs:IV. Menopause:- Has occurred when menses have ceased for an entire year- There is no equivalent to menopause in males- Declining estrogen levels ®o Atrophy of reproductive organs and breastso Irritability and depression in someo Hot flashes as skin blood vessels undergo intense vasodilation o Gradual thinning of the skin and bone losso Increased total blood cholesterol levels and falling HDLV. Development and Inheritancea. From Egg to Zygote:- The oocyte is viable for 12 to 24 hours- Sperm is viable 24 to 48 hours after ejaculation- For fertilization to occur, coitus must occur no more thano Two days before ovulationo 24 hours after ovulation- Fertilization: when the sperm’s chromosomes combine with