BIO10004 WK11

• Reproductive system


  System responsible for sexual reproduction and production of offspring
• Female reproductive system


  • Ovaries
  • Uterine tubes
  • Uterus
  • Vagina

  
• Function of female reproductive system


  • Produces sex hormones and functional gametes
  • Protects and supports developing embryo
  • Nourishes newborn infant

  
• Uterus


  Thick walled muscular organ that facilitates development of embryo and fetus
• Cervix


  Opens inferiorly into vagina
• Uterine tubes


  Project laterally and open adjacent to ovaries

  
• Vagina


  Thick walled muscular tube that serves as a passage for menses, birth canal and receives penis and ejaculate during intercourse
• Layers of uterus body


  • Perimetrium
  • Myometrium
  • Endometrium
• Endometrium


  Inner lining that supports pregnancy, actively involved in the menstrual cycle, shed if conception does not occur, highly vascular

  
• Uterine tubes


  Fimbriated infundibulum facilitates collection of oocytes

  
• Ovaries


  • Located adjacent to lateral wall of pelvis
  • Attached to uterus by ligament of ovary
  • Releases an oocyte during every menstrual cycle between puberty and menopause

  
• Fertilization and implantation


  1. Oocyte released from ovary

  2. Travels through uterine tube

  3. Fertilized by sperm

  4. Implants in uterine endometrium

  
• Ovarian cycle


  1. Monthly process of maturation, ovulation, and degeneration of tertiary ovarian follicle

  2. Divided into follicular phase and luteal phase

  
• Uterine cycle


  1. Menstrual phase - degeneration & shedding of functional endometrial

  2. Proliferative phase - rapid growth of new endometrial tissue, stimulated by estrogen

  3. Secretory phase - uterine glands secrete most after ovulation
• Ovarian and uterine cycles


  • Menstrual and proliferative phases occur during ovarian follicular phase
  • Secretory phase occurs during ovarian luteal phase (postovulation)

  
• Female external genitalia


  • Vulva/pudendum includes the erectile tissues and overlying skin
  • Labium minus - two thin folds of skin either side of midline
  • Vestibule - area between labium minus containing openings of urethra and vagina
  • Labium majus - larger fold of skin, over the vestibule and lateral to labium minus

  
• Mammary glands


  • Specialized organs of integumentary system
  • Produce milk (lactation) to nourish infant
  • Controlled by hormones
• Nipple


  Contains ducts of mammary glands
• Areola


  Reddish-brown skin around each nipple
• Male reproductive organs


  • Gonads: Testes
  • Ducts: Epididymis, ductus deferens, urethra
  • Accessory glands: Seminal vesicles, prostate, bulbourethral gland
  • External genitalia: Scrotum, penis

  
• Testis


  Located in the scrotum, contains seminiferous tubules surrounded by thick connective tissue (tunica albuginea), spermatozoa are produced in seminiferous tubules, collected in the rete testes and stored in epididymis until ejaculation
• Epididymis


  Spermatozoa mature (acquire ability to move and fertilize an egg) while stored in epididymis

  
• Vas deferens


  Muscular duct (smooth muscle wall) which transports spermatozoa to ejaculatory duct, part of spermatic cord, penetrates abdominal wall, descends along lateral wall of pelvic cavity to meet duct of seminal vesicle to form ejaculatory duct
• Accessory glands


  • Seminal vesicles, prostate, bulbourethral glands
  • Contribute to the volume of semen (seminal fluid)
  • Each have different secretions with different functions
• Penis


  Body is pendulous and entirely surrounded by skin, pelvic structures form attachment for roots of external genitalia, glans penis located at the head

  
• Erectile tissues of penis


  • Consist of two Corpora Cavernosa and a single Corpus Spongiosum
  • Urethra enters corpus spongiosum, thus it opens at glans penis
  • Erection is mediated by parasympathetic nervous system which relaxes arteries in penis, allowing blood to fill erectile tissues
• Urinary System


  Produces and eliminates urine
• Urinary System


  • Excretion
  • Removal of metabolic wastes from body fluids
  • Elimination
  • Discharge of wastes from body
  • Homeostatic regulation of volume and solute concentration of blood
• Kidney


  Produces urine and regulates homeostasis
• • Kidneys receive 20-25% of total cardiac output
  • About 1.2 L of blood flow through kidneys each minute
• Renal arterial supply


  Renal artery
• Nephron


  Microscopic functional units of kidneys

  
• Types of nephrons


  • Cortical nephron
  • Juxtamedullary nephron
• Nephron


  • Renal corpuscle (Glomerular capsule, Glomerulus)
  • Renal tubule (Proximal convoluted tubule, Nephron loop, Distal convoluted tubule)

  
• Glomerular Filtration


  1. Filtration occurs exclusively in the renal corpuscle, across the filtration membrane

  2. Podocytes: Large cells that wrap around glomerular capillaries
• Urine Formation


  1. Filtration in renal corpuscle

  2. Reabsorption in proximal convoluted tubule, descending thin limb, distal convoluted tubule, collecting duct

  3. Secretion in distal convoluted tubule
• Ureter


  Tube that transports urine from kidney to bladder
• Urinary Bladder


  Hollow viscus with strong muscular walls, stores urine
• Urethra


  Tube that transports urine from bladder out of the body
• Female Urethra


  • Short (~4cm long)
  • Orifices and normal narrowing sites
  • Pass through the pelvic floor and perineal membrane
  • Distensible (contain more elastic tissues/smooth muscles than male urethra)