Contraception and STI’s

• What are the major differences between spermatogenesis and oogenesis?


  • Oogenesis has uneven meiotic division, producing 1 secondary oocyte and 3 polar bodies.
  • Spermatogenesis produces four mature sperm.
  • Sperm production is continuous in males, while females are born with all primary oocytes.
  • Oogenesis includes long resting periods, while sperm is produced in an uninterrupted sequence.
• What is the oocyte in an ovarian follicle?


  The immature ovum suspended at metaphase of meiosis II
• What is the function of the zona pellucida?


  It binds sperm and induces the acrosome reaction
• Where does fertilization typically occur?

  In the upper region of the Fallopian tube
• How long is the ova viable after ovulation?


  Approximately 24 hours
• How long are sperm viable after ejaculation?


  1. 5 days
• What is required for sperm to penetrate the corona radiata?


  Many sperm are needed to break down the corona radiata
• What happens when the sperm nucleus enters the oocyte?


  The nucleus of the oocyte completes meiosis and the nuclei fuse
• What must happen for sperm to become motile?


  They must swim to the top of the correct Fallopian tube
• How do secretions of the cervix change at ovulation?


  They become sperm-friendly
• What is released from the acrosome upon the arrival of sperm at the secondary oocyte?


  Enzymes that digest through the zona pellucida
• What is the pathway of sperm from the testes to fertilization?


  1. Testes
  2. Vas deferens
  3. Urethra
  4. Penis
  5. Vagina
  6. Uterus
  7. Fallopian tubes
• What are the differences between sperm and ova?


  • Sperm: Small, motile, produced continuously, numerous.
  • Ova: Large, non-motile, produced in limited quantity, undergoes meiotic division.