Ch 46 CVHS

 Sexual : Fusion of haploid gametes: zygote  Asexual : No fusion of sperm & egg  Fission  Parent separates  Budding  new organisms grows off of the parent  Parthenogenesis  Egg develops w/out fertilization  Haploid or Diploid offspring

 specific times of year  Sheep, deer, lions  Sexually on a regular cycle  Humans (ovulate monthly)  Asexually or Sexually  Daphnia (depending on environmental conditions)  Asexually only  Fission, budding, parthenogenic (may switch sexes)  Hermaphroditisim  Both sexes, typically sessile (stationary) organisms

 External  Outside organism’s body  Requires moist environment  Amphibians, egg will desiccate if dry  Parental Care:  Usually none, offspring fend for themselves, many more produced than survive  Exceptions: some insects, some fish  Gamete Delivery:  Eggs and sperm released in environment simultaneously  Requires signals  Chemical  Day Length  Temperature  Internal  Sperm placed in (or near) female reproductive tract  Parental Care:  Usually significant care, most survive  Embryo protection from predation & water-loss:  Maternal body  Egg w/ Calcium & protein shell  Gamete Delivery:  Produced inside body  May have gonads or may use body wall  Courtship behavior, pheromones

 Complex reproductive systems (highly variable)  Female has ovaries  May have spermatheca (stores sperm, komodo dragons have one)  Male has testes and penis

 Testes  Site of gamete production  Scrotum  Holds testes in place & maintains temp 2 ْْْ C below body temp  Epididymis  Sperm mature & become motile  Vas Deferens  Muscular duct, propels sperm  Ejaculatory Duct  Further propels sperm  Urethra  Common reproductive & excretory opening extends length of penis  Accessory Glands  Seminal vesicles, prostate gland & bulbourethral glands Seminal Vesicles: 60% volume of semen, alkaline, fructose, prostaglandins (local regulators) Prostate Gland: anticoagulant & citrate Bulbourethral: mucus, neutralize acid in urine, contain live sperm

 Mitotic Spermatogonial Cell (2n)  Mitotic Speratogionium (2n)  Mitotic 1 ْ spermatocyte(2n)  Meiosis I 2 ْ spermatocyte (n)  Meiosis II Early Spermatocyte (n)  Extensive changes to become sperm

 Hypothalmus  GnRH: stimulate anterior pituitary to release FSH & LH  Anterior Pituitary  FSH  Sertoli Cells in testes (nourish sperm )  Inhibin: stops production of FSH by anterior pituitary  Spermatogenesis, when coupled w/ testosterone  LH  Leydig Cells in testes (produce androgens)  Testosterone (steroid hormone)  Two Negative Feeback Loops  Inhibin: Inhibits Anterior Pituitary  Testosterone: inhibits Hypothalmus & Anterior Pituitary

 Ovaries  Contain follicles where oocyte matures  Corpus Luteum: secretes estradiol & progesterone  Degenerates if egg is not fertilized  Oviduct  Pathway from ovary to uterus  Uterus  Muscular organ where fetus develops  Endometrium, lining, nourishes and protects fetus  Cervix  Opening to the uterus  Vagina  Muscular, flexible chamber where sperm are deposited  labia minora & labia majora, opening of vagina

 Mitosis Oogonium (2n)  Mitosis 1 ْ Oocyte (2n) prophase I of meiosis  Meiosis I & II 2 ْ Oocyte (n)  Ovulation & sperm entry Meiosis II completion Ovulation

 Uterine or Menstrual Cycle (changes in uterus)  Menstrual Flow: endometrium shed  Proliferative: regeneration & thickening of endometrium  Secretory: endometrium thickens further, glands secrete nutritional glycogen OR menstrual flow phase

 Ovarian Cycle (changes in ovaries)  Follicular: Several follicles in ovaries grow  Ovulatory: Follicle & adjacent wall of ovary rupture & release 2 ْ oocyte  Luteal Phase: Remaining follicular tissue becomes CORPUS LUTEUM which is endocrine tissue that secretes hormones

 Increased estrogen secreted by follicle stimulates endometrium to thicken: Proliferative Phase  After Ovulation, estrogen & progesterone secreted by the CL stimulate development of endometrium: Secretory Phase  Decrease Estrogen & progesterone due to CL breakdown reduces blood to endometrium and menstrual flow begins  If embryo present, it secretes HCG which maintains estrogen & progesterone so endometrium is maintained

 Cessation of ovulation & menstruation  Ages 46 to 54  Ovaries lose repsonse to FSH & LH secreted by the anterior pituitary  Decline in Estrogen production

 Fertilization: sperm fuses w/ egg in oviduct  Female Reroductive tract produces secretions which capacitate sperm cells  The sperm releases enzymes to penetrate the Zona Pellucida

 Cleavage : zygote begins to divide 24 hrs. later  Blastocyst forms  Once implanted, embryo releases hCG (human chorionic gonadotropin) acts like a LH to maintain estrodial and progesterone levels  Trophoblast begins to form  Becomes part of endometrium to nourish fetus

 1 st Trimester: 2-4 weeks, embryo obtains nutrients from endometrium  Placenta developing  Organogenesis  2 nd Trimester: Fetus secrets progesterone to maintain pregnancy  CL deteriorates  Fetus is nourished through Placenta(material & fetal blood vessels for exchange of nutrients to fetus and wastes to mother)  3 rd Trimester: Fetus puts on length & mass, pushes agains mother’s internal organs

 High Estrogen levels during last weeks of pregnancy trigger formation of oxytocin receptors in uterus  Oxytocin secreted by fetus & posterior pituitiary stimulate smooth muscle contractions of uterus  POSITIVE FEEDBACK!  Prolactin stimulates milk production

 Rhythm  timing intercourse when conception is least likely (5 days before & after ovulation)  IUD  Prevents implantation  Pills  Estrogen & Progesin: prevent ovulation  Progestin: increases vaginal secretions, prevents sperm movement  Morning After: Prevents implantation  Barriers  Condoms: some protection against STD’s  Diaphragm: prevents sperm from reaching oviduct  Sterilization:  Cuts pathway for egg or sperm  Oviducts  Vas Deferens