Power Point 1 Male Reproductive System Objective 1 Explain the parasympathetic and sympathetic innervations of the male reproductive system and the effects of each Parasympathetic causes erection Stimulates increase in NO Causes relaxation and vasodilation of arterioles Erectile bodies corpus cavernosa and spongiosa fill with blood Parasympathetic also causes stimulation of bulbourethral glands this lubricates the glans penis Sympathetic causes ejaculation Ejaculation is the propulsion of semen from the male duct system SNS stimulates the spinal reflex Contraction of the ducts and glands Constriction of the bladder Contraction of bulbospongiosis muscles Think of Point parasympathetic and Shoot sympathetic Objective 2 Describe the exocrine and endocrine function of the testes Example Sertoli and Leydig cells The testes serve 2 distinct physiological roles Exocrine function production of mature sperm spermatogenesis involves the seminiferous epithelium and Sertoli Cells Endocrine function production of androgens steriodogenesis involves the interstitial compartment and Leydig Cells Objective 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 takes place in the seminiferous tubules of the Testes Produces sperm gametes or spermatozoa 400mil sperm are produced each day since person is 14 years old A sperm is haploid n meaning it has 23 pairs of chromosomes when it combines with the female ovum n it becomes diploid 2n meaning it has 46 pairs of chromosomes Gamete formation in both sees involves meiosis which occurs in the gonads Spermatogenesis Most cells making up the epithelial walls of the seminiferous tubules are in various stages of cell division These cells are collectively called spermatogenic cells Proliferative phase 3 types of spermatogonia Type A dark Ad Dense chromatin gives rise to type Ap as well as generating more of itself Type A pale Ap chromatin is less dense give rise to type B Type B Type A stay in the basal lamina and Type B get pushed toward the lumen to become a primary spermatocyte Meiotic Phase Meiosis I Type B divide by mitosis to primary spermatocytes replicated chromosomes seek out a partner After Meiosis 1 each daughter cell has 2 copies and the number of the chromosomes are cut in half 46 23 chromosomes these are secondary spermatocytes Meiosis II Spermiogenic Phase The spermatocyte undergoes further division as a haploid and become early spermatids differentiation of a spermatid into a sperm through 4 steps 1 Golgi Phase tail filament appears head cap appears from acrosomal granule 2 Cap phase 3 Acrosome phase 4 Maturation phase a a a a cell completes differentiation to become a mature sperm nucleus and head cap elongate and acrosomal granule differentiates to form acrosome lumen another 10 days is required for movement into the epididymis Spermatogonia initiate a new cycle every 16 days and there are 4 cycles 64 days Once sperm are released into total of 74 days sperm are stored in the epididymis Objective 4 Explain the hormonal control of spermatogenesis as it related to FSH and LH FSH and Testosterone are both required for regulation of spermatogenesis FSH binds to receptors in Sertoli cells and thus helps to initiate spermatogenesis also causes an Sertoli cells to secrete ABP androgen binding protein which keeps testosterone concentrations high FSH also increases the of LH receptors on Leydig cells causing an increase in testosterone production which maintains spermatogenesis The hypothalamus releases GnRH which controls the release of FSH and LH Binding of GnRH to pituitary cells prompts them to secrete FSH and LH Objective 5 Explain the role of the epididymis and where the ejaculate comes from Sperm migration through the epididymis takes about 10 16 days adding this to the time for spermatogenesis 74 days 90 days for mature sperm to appear in ejaculate Sperm are stored in the epididymis and vas deferens NOT seminal vesicles Sperm acuire capacity for motility in the epididymis aged sperm are eliminated via phagocytosis Order or ejaculation Cowper Littre clear fluid which lubricates the urethra 5 of ejaculate Prostate liqufiys the ejaculate PSA activates sperm motility 15 30 of ejaculate ampula of vas deferens epididymis containing sperm seminal vesicles 45 80 of ejaculate Power Point 2 Female Reproductive System Objective 1 Explain the time frame of oogenesis Ovaries are the primary female reproductive organs produce female gametes ova secrete female sex hormones estrogen and progesterone Oogenesis in the fetal period oogonia stem cells this process produces female sex cells Oogonia divided by mitosis are transformed into primary oocytes primary oocytes begin meiosis but most don t complete it Oogonia peak at 20 weeks and then undergo meiosis then the number greatly diminishes Oogenesis begins at 6 8 weeks reaching 6 7 mil oogonia primordial follicles by 16 20 weeks maximum oogonia content of gonad The store of oocytes finally becomes depleted about 50 years later women will have all of the eggs she will ever need by 20 weeks in the womb therefore having children over the age of 35 40 could cause abnormalities Objective 2 DETAIL the ovarian cycle Explain each phrase 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 that is the bulk and objective of this presentation Ovarian cycle monthly series of events associated with the maturation of an egg It is composed of 2 phases Follicular phase Luteal phase period of follical growth 1 14 d perios of corpus luteum activity 14 28d Ovulation occurs midcycle Length of cycles can vary from 21 days to 40 days The Luteal phase remains constant at 14 days The follicular phase will vary The follicular phase FSH follicle stimulating hormone rest undergo degeneration on the follicle develops about 20 follicles at the begining of the cycle but only 1 develops and the The developing follicle has enough estrogen to be maintained due to theca and granulosa cells theca cells make androgens which are transferred to granulosa cells to make estrogen Two cell theory LH induces androstenedione synth in theca cells driven by the FSH stimulus granulosa cells process androstenedione into estrone which is further converted into estradiol Steps of the Follicular
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