A&P: CH.27 [Reproductive System]

• primary sex organs are the testes and ovaries; they produce gametes and secrete various steroid hormones aka sex hormones
• ducts, glands, and external genitalia are accessory reproductive organs
• zygote: fertilized egg that has not yet undergone mitosis
• sex hormones- androgens in males and estrogens and progesterone in females- play roles in development and function of reproductive organs and sexual behavior/drive
• sperm delivery

  • testes
  • epididymis
  • ductus deferens
  • ejaculatory duct
  • urethra
• accessory sex glands: seminal glands, prostate and bulbo-urethral glands
• viable sperm cannot be produced in abundance at 37 degrees celsius so the scrotum is outside the body cavity
• dartos muscle: smooth muscle in superficial fascia that wrinkles scrotal skin
• cremasteric muscles: skeletal muscle that contract to raise or lower testes
• seminiferous tubules: site of sperm production (meiosis)
• myoid cells contract rhythmically to squeeze sperm and testicular fluids from testes through tubules
• interstitial cells produce testosterone which stimulates spermatogenesis
• epididymis: coiled tube where sperm mature and are stored
• vas deferens: carries sperm from epididymis into urethra
• seminal gland: secretes alkaline fluid that neutralizes acidity of urine and provides nutrients for sperm
• bulbourethral glands: secrete mucus to lubricate penis during ejaculation while neutralizing urine traces
• prostate gland: secretes fluid that makes up semen, located below bladder; activates sperm
• spermatic cord: connects the testes to the abdominal wall
• corpus spongiosum: surround urethra
• corpora cavernosa: erectile portion where blood flows into
• prostatitis: inflammation of the prostate gland
• benign prostatic hyperplasia: hypertrophy of prostate causing staining during urination
• spermatogenesis: the process of sperm production in the testes by the seminiferous tubules
• human diploid chromosomal number is 46
• diploid cells contain 23 pairs of chromosomes, one from each parent
• haploid cells have only half the normal amount of DNA (1 set) found in somatic cells
• gametes are haploid cells that fuse to form zygotes which are diploid
• in meiosis two divisions occur but DNA replication does not occur
• during the second division of meiosis, sister chromatids separate so there are now four genetically distinct daughter cell which are genetically different from mother cell
• meiosis produces cells for reproduction and introduces genetic variability and reduces chromosomal number by half so when fertilization occurs the normal diploid chromosomal number is restored
• male reproductive structures

  A) seminal gland

  B) ejaculatory duct

  C) bulbo-urethral gland and duct

  D) bulb of penis

  E) crus of penis

  F) bulbo-urethral duct opening

  G) ductus deferens

  H) corpora cavernosa

  I) epididymis

  J) corpus spongiosum

  K) prostate

  
• sagittal view of reproductive male organs

  A) prostatic urethra

  B) corpus cavernosum

  C) corpus spongiosum

  D) glans penis

  E) prepuce

  F) scrotum

  G) testis

  H) epididymis

  I) ductus deferens

  J) bulbo-urethral gland

  K) prostate

  L) ejaculatory duct

  M) ampulla of ductus deferens

  N) seminal gland

  
• ovaries produce ova, estrogens and progesterone
• female accessory ducts are uterine tubes, uterus, and vagina
• ovarian ligament anchors ovary medially to uterus
• suspensory ligament anchors it laterally to pelvic wall
• mesovarium suspends it in between ovarian and suspensory ligaments
• suspensory and mesovarium part of broad ligament
• within ovarian follicles are immature eggs called oocytes
• primordial follicles have a single layer of follicle cells around the oocyte