A P Exam 4 Objectives Power Point 1 Male Reproductive System 1 Explain the parasympathetic and sympathetic innervations of the male reproductive system and the effects of each PNS SNS o stimulates increase in NO nitrous oxide o relaxation and vasodilation of arterioles o erectile bodies fill with blood o this causes erection o stimulates spinal reflex o contraction of ducts and glands o constriction of bladder o contraction of bulbospongiosus muscles o this causes ejaculation propulsion of semen from male duct system 2 Describe the exocrine and endocrine function of the testes Example Sertoli and Leydig cells exocrine function production of mature sperm spermatogenesis involves seminiferous epithelium and Sertoli cells endocrine function production of androgens steroidogenesis involves interstitial compartment and Leydig cells 3 Explain IN DETAIL the entire process of spermatogenesis as we described in class what happens in each phase and it s time frame through the seminiferous epithelium spermatogenesis production of sperm gametes spermatozoa that takes place in seminiferous tubules of testes o begins at about age 14 and makes 4 million sperm per day o Proliferative Phase o Meiotic Phase Type A dark Ad spermatogonia dense chromatin Type A pale Ap spermatogonia less dense chromatin Type B Ad gives rise to Ap as well as generates more Ad for future generations of sperm Ap gives rise to B Meiosis I type B divides by mitosis to primary spermatocytes and replicated chromosomes seek out partner after each daughter cell has 2 copies and number of chromosomes is cut in half from 46 23 chromosomes Meiosis II further division of cells but chromosome number stays the same o Spermiogenic Phase differentiation of spermatid into sperm Golgi Phase tail filament phase Cap Phase head cap appears from acrosomal granule Acrosomal Phase nucleus and head cap elongate and acrosomal granule differentiates to form acrosome acrosome eats away at egg acrosomal reaction Maturation Phase cell completes differentiation to become a mature sperm Seminiferous Epithelium o Cells 1st cycle Type A gives rise to Type B 2nd cycle primary spermatocytes form 3rd cycle spermatids appear 4th cycle spermiogenesis completed and spermiation begins o Cycles complete spermatogonia initiate new cycle every 16 days so 64 days for all four cycles to once sperm is released into lumen another 10 days are required for movement to epididymus total of 74 days sperm are stored in the epididymus 4 Explain the hormonal control of spermatogenesis as it relates to FSH and LH FSH and testosterone are both required for regulation of spermatogenesis FSH binds to receptors in Sertoli cells to help initiate spermatogenesis which also causes an FSH also causes an increase in number of LH leutenizing hormone in Leydig cells causing increase in ABP testosterone production to increase this maintains spermatogenesis 5 Explain the role of the epididymis and where the ejaculate comes from flow of sperm epididymus ductus vas deferns ejaculatory duct urethra epididymus stores mature sperm o sperm migration through epididymus takes about 10 16 days o takes about 90 days time include spermatogenesis and migration for mature sperm to appear in ejaculate Seminal plasma and semen o sperm mature and acquire the capacity for motility in epdidymus o seminal plasma secretions from sex accessory glands seminal vesicles prostate Cowper s bulbourethral glands ampulla of vas deferens o semen combination of seminal plasma and sperm o order of ejaculation Cowper gland ampulla of epididymus holding sperm seminal vesicles o sperm may be present in pre ejaculatory fluid but small amount o Cowper s gland 5 of ejaculate may contain small amount of sperm clear fluid rich in mucoproteins lubricates distal urethra o Prostate gland 15 30 of ejaculate contains citric acid acid phosphatase calcium and zinc liquefies ejaculate PSA prostate specific antigen helps activate sperm motility no sperm comes from this portion o Seminal vesicles 45 80 of ejaculate rich in fructose and prostaglandins prostaglandins cause smooth muscle relaxation and contraction to propel ejaculate contains enzymes that cause coagulation of ejaculate absence of fructose used to diagnose absence of vas deferens in epididymus infertility stages of sexual maturity in males Tanner stages 5 stages Power Point 2 Female Reproductive System 1 Explain the time frame of oogenesis oogenesis takes place during the fetal stage of life and is the process of producing female sex cells o oogonia stem cells oogonia divided by mitosis are transferred into primary oocytes primary oocytes then begin meiosis but do not complete it oogonia peak at 20 weeks then undergo meiosis then the number of oogonia greatly diminishes o women will have all the eggs she need by 20 weeks in mother s womb oogenesis begins at 6 8 weeks reaching 6 7 million oogonia primordial follicles by 16 20 weeks max oogonial content of gonad store of oocytes finally becomes depleted about 50 years later 2 DETAIL the ovarian cycle Explain each phase time frames estrogen production hormone level fluctuation body temperature the hypothalamic pituitary axis stimulation of these hormones and explain all graphs in detail understand all graphs this is the bulk of this objective and presentation Establishing the ovarian cycle o during childhood ovaries grow and secrete small amounts of estrogen that inhibit the hypothalamic release of GnRH gonadotrophin releasing hormone o as puberty nears GnRH is released from the hypothalamus stimulating release of FSH and LH from pituitary and these act on the ovary FSH causes maturation and maintenance of follicles LH surges at ovulation day 14 and forms corpus luteum o fatty tissue increase is also associated with puberty which results in an increase in leptin which also influence the hypothalamus o these events will continue until menarche first menstrual cycle a woman has Follicular phase period of follicle growth days 1 14 o time frame may vary length of cycles can vary from 21 40 days depending on the woman o FSH follicle stimulating hormone develops about 20 follicles at beginning of each ovarian cycle but only one develops and the rest atresia degenerate o developing follicle has enough estrogen to be maintained due to theca cells and granulose cells on follicle theca cells make androgens which are transferred to granulose cells to make estrogen 2 cell 2 gonadotrophin theory LH induces androstenedione synthesis in
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