Human Reproductive Systems Male Reproductive System • Testes: male gonads – Form male gametes (sperm) in ________________________ • Scrotum: sac that holds testes outside of body cavity – Sperm develop optimally ____________________________ ____________________________________. • Epididymus: _______________________ to mature • Penis: – fleshy tube with ____________ allowing to internal fertilization • Vas Deferens: – carries sperm ______________ ____________ during ejaculation • Semen: – transport medium for sperm – Made up nutrient fluid to nourish and protect sperm in female reproductive tract • Urethra: – tube where semen exits penis – Shares same structure with _____________________ • Vasectomy: – _______________________, preventing sperm from leaving the body • Testosterone: – produced by _____________ – plays a role in development of male secondary sex characteristics • FSH and LH: – secreted by ______________ – help in growth and development of sperm in testes Female Reproductive System • Ovaries: female gonads – Produce eggs – Secrete _______________ – Each contains about 200,000 tiny egg sacs called __________ – One egg is released each month during ____________________ – Estrogen: • causes development of female secondary sexual characteristics • Breast development, broadened pelvis, distribution of body fat • Fallopian Tubes or Oviducts: – near each ovary but not directly connected to it – ____________line tube and create current that draws the released egg towards uterus – Where egg is __________________ • Uterus: – thick walled muscular organ where a fertilized egg will implant and grow • Cervix: – narrow _____________________ • Vagina: – ____________________, site where sperm is deposited • Note: Urinary and reproductive tracts are separate in females Menstrual Cycle Series of hormonally controlled changes that occur to the ovary and uterine lining • Basic Steps of Cycle: – Egg matures and erupts from its follicle entering fallopian tube. – Wall of the uterus has __________________ with a rich supply of blood vessels (endometrial lining) and is prepared to receive a fertilized egg – If egg not fertilized, lining breaks down and passes from the body as menstrual fluid and cycle begins again Stages of Menstrual Cycle • Controlled by _____________________________ – Brain (FSH & LH) and ovary (estrogen & progesterone) • Follicle Stage (10-14 days) – _____________________ follicle stimulating hormone (FSH) causing follicle in ovary to mature – ____________ gets secreted by follicle in ovary as it develops, causing uterine lining to thicken • Ovulation (middle of cycle) – Increased estrogen causes pituitary to lower FSH and begin secreting _______________ (LH) – When this reaches certain level ovulation occurs and __________ ________________ releasing egg – Egg must be fertilized in about 24 hours or it dies • Corpus Luteum Stage (10-14 days) – Ruptured follicle forms corpus luteum (yellow body) which secretes ______________________ – Progesterone maintains the _________________________ • Menstruation (3-5 days) – If fertilization doesn’t happen, LH secretion decreases, corpus luteum breaks down and ________________drops – Uterine lining is no longer maintained and ______________ and is released as ____________________ Menopause: the permanent cessation of the menstrual cycle Human Fertilization & Development • Fertilization: (Internal) – ejaculation of _________________________ into vagina – sperm swim through cervix into uterus and into Fallopian tube where fertilization takes place – one sperm breaks through membrane surrounding egg and fuses with egg nucleus forming ___________________ • Gestation: the period of development ____________________ In Vitro Fertilization Egg is fertilized with sperm _______________ then placed into uterus several days later where it can implant Embryo Development • In Fallopian Tube: – fertilization occurs – ____________ occurs – ________ and ________ stage http://www.dnatube.com/video/1127/Human-Reproduction-Fertilization-and-Fetal-Development is reached • In Uterus – ______________ occurs – embryo attaches itself to the lining of uterus – _______________ and __________________occur – Forms 3 layers from which different tissues develop • Ectopic Pregnancy – Sometimes the embryo implants someplace other than uterus (in oviduct or even in the abdomen). This often results in the death of the embryo and or the mother. • Fraternal Twins: – fertilization __________________ • Identical Twins: Multiple Embryos – __________________ and splits into two separate embryos – Conjoined Twins: when identical twins don’t separate completely Protecting & Nourishing Embryo • Chorion: – forms small fingerlike projections called _______________ that extend into uterine lining • Placenta: – uterine lining and chorionic villi come together – villi constantly bathed in ______________ – exchange of nutrients, oxygen and wastes takes place here • Umbilical Cord: – rope like structure connects developing fetus to placenta • Amnion: – membrane sack surrounding fetus – filled with ___________________ – protects fetus from shock • Amniocentesis: – testing amniotic fluid for chromosomal and developmental disorders • Labor: – uterine muscles _________ – opening to cervix gets larger Labor & Birth • Eventually amniotic sac bursts open and baby passes through birth canal • Shortly after the ________ or “afterbirth” is expelled http://www.youtube.com/watch?v=BgZ5z6RB06c&safe=active • Nova: The Miracle of Life • http://www.youtube.com/watch?v=Wou1Udu_vr8 &safe=active • Nova: Life’s Greatest Miracle • http://www.youtube.com/watch?v=swYuEkzTkV0 &safe=active • Excellent for extra credit!! • And both are related to your test!!