Reproduction

• Gamete


  Sex cell
• reproductive system functions

  • gamete (sex cell) production
  • internal fertilization (for sperm and egg to meet and make a zygote, the first offspring cell)
  • Embryo maintenance
• Chapter 28: Reproductive system


  Includes production, fertilization, and maintenance
• Cell division


  1. Nuclear division

  2. Mitosis

  3. Meiosis

  4. Cytokinesis
• Mitosis


  1 parent cell produces 2 identical daughter cells (46 chromosomes)
• Meiosis


  1 parent cell produces 4 different haploid daughter cells (23 chromosomes)
• Meiosis1


  • Reductional division to reduce total by half
• Female Reproductive System


  Located in pelvic cavity, contains organs with digestive, reproductive and urinary functions
• Ovary


  • Primary organ that produces gametes and hormones
  • Surrounded by protective connective tissue
  • Divided into outer cortex and inner medulla
• Ovarian follicle development


  • Primordial follicle
  • Primary follicle
  • Secondary follicle
  • Antral follicle
  • Mature follicle
  • Corpus luteum
  • Corpus albicans
• Primary oocyte


  Paused in Prophase 1
• Secondary oocyte


  Paused in Metaphase 2
• Ovarian follicle


  • Contains oocyte and follicular cells
  • Follicular cells secrete estrogen
  • Thecal cells produce androgens
• 1 mature follicle per month will ovulate
• Corpus luteum


  Secretes progesterone and estrogen, builds up uterine lining
• Corpus luteum lasts 10-13 days if egg is not fertilized
• Human reproductive system is primarily non-functional until Puberty
• Onset of Puberty


  1. Hypothalamus secretes GnRH

  2. Anterior pituitary releases FSH and LH

  3. Gonads produce sex hormones
• Ovarian cycle


  1. Hypothalamus secretes GnRH

  2. Follicular development

  3. LH surge triggers ovulation

  4. Corpus luteum forms and secretes hormones

  5. Corpus luteum regresses if no fertilization
• Uterine cycle


  1. Menstrual phase

  2. Proliferative phase

  3. Secretory phase
• Menstrual cycle is always 14 days after ovulation
• Fertilization and implantation


  1. Fertilized egg travels to uterus

  2. Blastocyst implants in uterine lining
• Uterine wall composition


  • Perimetrium (outer)
  • Myometrium (muscle)
  • Endometrium (mucosa)
• Vagina


  Passageway with mucosa, muscularis, and adventitia layers
• Female genitalia functions


  • Protection
  • Assistance in intercourse
• Male Reproductive System


  Testes produce gametes and hormones
• Testes


  Primary organ that produces hormones and gametes
• Testes


  • Located in the scrotum
  • Have a tunica vaginalis
  • Painless
  • Maintained at 93.2°F for normal sperm development
  • Have a tunica albuginea (fibrous membrane)
  • Divided into lobules with 1-4 seminiferous tubules
• Interstitial cells (Leydig cells)


  Produce androgen
• germs cells undergo:

  1. Spermiogenesis (anatomical changes to resemble a sperm). 2. meiosis
• Sustentacular cells (Sertoli cells)


  • Nourish and form the blood-testes barrier
  • Produce inhibin (regulates sperm production)
• Hypothalamus releases GnRH


  Anterior pituitary releases LH and FSH
• LH acts on interstitial cells


  Increases androgen production
• FSH acts on sustentacular cells


  Increases testosterone concentration in testes, stimulating spermatogenesis (meiosis), stimulates spermatogenesis (anatomical change to resemble a sperm)
• Epididymis


  Completes 2-week sperm development to gain the ability to swim. storage of mature sperm
• Ducts (sperm path)


  • Epididymis
  • Ductus (vas) deferens
  • Ejaculatory duct
  • Urethra
• Seminal vesicles


  Produce alkaline fluid with fructose, prostaglandins, calcium, zinc, and clotting enzymes to nourish and protect sperm
• Prostate gland


  Produces PSA (liquefying enzyme)
• Bulbourethral glands


  Produce mucus for pre-ejaculation
• Penis


  • Contains erectile bodies (corpora cavernosa and corpus spongiosum)
  • Erection occurs due to blood filling the erectile bodies and veins compressing