BIO181 Reproduction

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BIO181 Reproduction
2012-04-25 00:57:32

Mossman's 181 Lecture on Reproduction
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  1. What are the major differences between oogenesis and spermatogenesis in humans?
    In spermatogenesis, 4 gametes are produced from each meiotic division, whereas in oogenesis there is only 1 gamete produced from each division
  2. Briefly describe the steps in reproduction in humans?
    • ␣ produce the genetic material necessary for
    • creating the offspring
    • ␣ combine the maternal and paternal genetic material
    • ␣ support the developing offspring until they can tolerate the external environment (with or without assistance from the parents)
    • ␣ deliver the offspring into the environment
    • ␣ support the offspring in the environment until they are independent
  3. Name the glands in the male reproductive tract contributing to semen.
    • Sperm are produced in seminiferous tubules
    • • Sperm mature in the epididymis
    • • Sperm delivered to the urethra through the vasa deferentia
    • Other components of semen are produced in the seminal vesicles, prostate gland, and bulbourethral glands.
    • Penis
  4. Where in the seminiferous tubule are spermatogonia located?
    Near the base membrane

  5. What is the function of Leydig cells?
    To secret testosterone, which initiates spermatogenesis
  6. At what stage of meiosis are primary spermatocytes in?
    Prophase or metaphase
  7. What hormone controls levels of testosterone?
    Leutenizing Hormone
  8. At what stage of meiosis are primary oocytes?
  9. Which hormone stimulates ovulation?
    FSH and LH
  10. What hormones maintain pregnancy?
    estrogen and progesterone
  11. Describe the changes in hormones that occur during the menstrual (uterine) cycle.
  12. Give an example of negative feedback in the female reproductive system.
    Regulation of gonadotropins
  13. Give an example of positive feedback
  14. What is the function of oxytocin in reproduction?
    It stimulates birth by increasing the frequency and intensity of uterine contraction
  15. How do birth control pills work?
    They release estrogen and progesterone into the body, "tricking" the body into thinking its already pregnant.
  16. How long is the normal ovarian cycle?
    28 Days
  17. When does ovulation occur?
    14 days
  18. What factors trigger birth?
    The onset ofl abor is due to many hormonal and mechanical factors, which increase contractility of uterine muscles.
  19. Where in the female reproductive tract does fertilization occur?
    Fertilization occurs in the upper regions of the oviducts
  20. Where does development of the blastocyst begin?
    The zygote becomes a blastocyst through cell divisions as it passes down the oviduct
  21. Blastocyst
    A thin-walled hollow structure in early embryonic development that contains a cluster of cells called the inner cell mass from which the embryo arises.
  22. Bulbourethral gland
    Either of two small glands that are located below the prostate and discharge a component of the seminal fluid into the urethra.
  23. Corpus luteum
    A yellow, progesterone-secreting mass of cells that forms from an ovarian follicle after the release of a mature egg.
  24. Endometrium
    The glandular mucous membrane that lines the uterus.
  25. Epididymis
    A long, narrow, convoluted tube, part of the spermatic duct system, that lies on the posterior aspect of each testicle, connecting it to the vas deferens.
  26. Estrogen
    Any of a group of steroid hormones that primarily regulate the growth, development, and function of the female reproductive system.
  27. Follicle-stimulating hormone
    a gonadotrophic hormone secreted by the pituitary gland that stimulates maturation of ovarian follicles in female mammals and growth of seminiferous tubules in males
  28. Human chorionic gonadotropin
    A hormone produced by the placenta that maintains the corpus luteum during pregnancy.
  29. Implantation
    The process by which a fertilized egg implants in the uterine lining.
  30. Leydig cell
    a cell in the testes that secretes the hormone testosterone
  31. Luteinizing hormone
    A hormone produced by the anterior lobe of the pituitary gland that stimulates ovulation and the development of the corpus luteum in the female and the production of testosterone by the interstitial cells of the testis in the male.
  32. Menstrual (uterine) cycle
    The recurring series of changes in women in which an egg is produced in the process known as ovulation, and the uterine lining thickens to allow for implantation if fertilization occurs. If the egg is not fertilized, the lining of the uterus breaks down and is discharged during menstruation.
  33. Oogonial cell
    a cell that arises from a primordial germ cell and differentiates into an oocyte in the ovary.
  34. Ovarian cycle
    • The maturation and release of ova
  35. Placenta
    A membranous vascular organ that develops in female mammals during pregnancy, lining the uterine wall and partially enveloping the fetus
  36. Primary Oocyte
    • A cell from which an egg or ovum develops by meiosis; a female gametocyte.
  37. Primary spermatocyte
    diploid cell that undergoes meiosis to form four spermatids. A primary spermatocyte divides into two secondary spermatocytes, which in turn divide to form the spermatids.
  38. Progesterone
    A steroid hormone secreted by the corpus luteum of the ovary and by the placenta, that acts to prepare the uterus for implantation of the fertilized ovum, to maintain pregnancy, and to promote development of the mammary glands.
  39. Prostate gland
    A gland in male mammals surrounding the urethra at the base of the bladder that controls release of urine from the bladder and secretes a fluid which is a major constituent of semen.
  40. Secondary oocyte
    An oocyte in which the first meiotic division is completed. The second meiotic division usually stops short of completion unless fertilization occurs.
  41. Secondary spermatocyte
    a haploid cell produced by meiotic division of the primary spermatocyte; it can then develop into the spermatid.
  42. Semen
    A viscous whitish secretion of the male reproductive organs, containing spermatozoa and consisting of secretions of the testes, seminal vesicles, prostate, and bulbourethral glands.
  43. Seminiferous tubule
    One of two or three twisted curved tubules in each lobule of the testis in which spermatogenesis occurs.
  44. Sertoli cell
    Any of the elongated striated cells in the seminiferous tubules to which spermatids attach during spermiogenesis.
  45. Sperm
    A male gamete or reproductive cell; a spermatozoon.
  46. Spermatogonial cell
    Any of the cells of the gonads in male organisms that are the progenitors of spermatocytes.
  47. Teratogen
    • An agent, such as a virus, a drug, or radiation, that causes malformation of an embryo or fetus.
  48. Testis
    the reproductive gland in a male , the source of spermatozoa and the androgens, normally occurring paired in an external scrotum
  49. Testosterone
    produced primarily in the testes and responsible for the development and maintenance of male secondary sex characteristics.
  50. Trophoblast
    The outermost layer of cells of the blastocyst that attaches the fertilized ovum to the uterine wall and serves as a nutritive pathway for the embryo.
  51. Vas deferens
    The main duct through which semen is carried from the epididymis to the ejaculatory duct.