2. Asexual Reproduction Without fusion of gametes Types: Fission – splitting into two Budding – new org grows off of another org Fragmentation – new org develops from piece of other org (accompanied by regeneration) Parthenogenesis – org develops from unfertilized egg (all offspring female)
3. Hermaphrodites Produce both egg and sperm 1⁰ly orgs that are sessile, burrow or are parasites May self fertilize, most cross fertilize Some sp have sequential hermaphrodism – ind reverses sex during its lifetime
4. Fertilization Union of egg and sperm May be: External: eggs released into wet envir then male fertilizes Internal: sperm is deposited in or near female reproductive tract Adaptation of terrestrial animals Pheromones – chem signals released by org that influence other membs of same sp
5. (Urinary bladder) Seminal vesicle (Rectum) (Pubic bone) (Urinarybladder) Seminal vesicle (behind bladder) Erectile tissue of penis Vas deferens Ejaculatory duct Prostate gland Prostate gland Urethra Bulbourethral gland Glans penis Bulbourethral gland Urethra Vas deferens Epididymis Testis Erectile tissue of penis Prepuce Scrotum Scrotum Vas deferens Epididymis Glans penis Testis Figure 46.10 Male Reproductive System Seminiferous tubules Leydig cells Baculum
7. Female Reproductive System Ovaries Follicle Ovulation Corpus luteum Oviduct Uterus Endometrium Cervix Vagina Vulva Labia majora/labia minora clitoris
8. Ovary Primary germ cell in embryo Differentiation Oogonium in ovary Oogonium 2n Mitotic division Primary oocyte within follicle Primary oocyte, arrested in prophase of meiosis I (present at birth) 2n Growing follicle Completion of meiosis I and onset of meiosis II n First polar body Secondary oocyte, arrested at meta- phase of meiosis II n Ovulation Mature follicle Entry of sperm triggers completion of meiosis II n n Ruptured follicle Ovum Ovulated secondary oocyte Corpus luteum Degenerating corpus luteum Figure 46.11 Spermatogenesis Continuous & prolific Occurs in seminiferous tubules 100-650 million sperm cells/ ejaculation Oogenesis Unequal cytokinesis Polar bodies degenerate Not throughout lifetime Lone resting periods Gametogenesis
11. Conception, Development & Birth Conception = fertilization 1 week blastocyst implants into endometrium Embryo secretes human chorionic gonadotropin (some is secreted in urine)
12. First Trimester Trophoblast placenta Organogenesis Heart beating – 4 wks All major structures of adult – 8 wks Heart beat by stethescope – end of first trimester Embryo fetus @ 8 wks 5cm long Changes in mom too
14. Third Trimester Fetus grows to 3-4kg & 50 cm long Fetal activity decreases due to space restraints Mom’s organs are compressed and displaced Freq urination, constipation, back aches
15. Labor & Birth Placenta Umbilical cord Uterus Cervix Dilation of the cervix 1 Expulsion: delivery of the infant 2 Uterus Placenta (detaching) Umbilical cord Delivery of the placenta Figure 46.19 3 Oxytocin Stages of Labor Lactation
16. Modern Reproductive Technology Fetal testing Congenetial disorders Aminocentesis Chorionic villi sampling Ultrasound Ethics? To terminate pregnancy Infertility Hormone therapy IUI (Intrauterine Insemination) IVF (In vitro fertilization) ZIFT (zygote intrafallopiantransfer) GIFT (gamete intrafallopian transfer) $1,000s/attempt
17. Female Male Event Event Method Method Production of viable sperm Production of viable oocytes Vasectomy Combination birth control pill (or injection, patch, or vaginal ring) Ovulation Sperm transport down male duct system Abstinence Abstinence Condom Coitus interruptus (very high failure rate) Sperm deposited in vagina Capture of the oocyte by the oviduct Tubal ligation Spermicides; diaphragm; cervical cap; progestin alone (minipill, implant, or injection) Transport of oocyte in oviduct Sperm movement through female reproductive tract Meeting of sperm and oocyte in oviduct Morning-after pill (MAP) Union of sperm and egg Progestin alone Implantation of blastocyst in properly prepared endometrium Figure 46.20 Birth