Reproductive System

• Male reproductive system

  Includes testes, ducts, accessory sex glands, and penis
• Functions of the male reproductive system

  • Produce sperm and testosterone
  • Transport, store, and mature sperm
  • Secrete liquid portion of semen
  • Ejaculate semen

  
• Testes


  • Produce sperm and testosterone

  
• Epididymis


  • Transports, stores, and assists in maturation of sperm

  
• Ejaculatory ducts


  • Eject sperm into the urethra
• Urethra

  • Passageway for ejaculation of semen and excretion of urine
• Seminal vesicles

  • Secrete alkaline, viscous fluid that constitutes about 60% of semen volume and contributes to sperm viability
• Prostate


  • Secretes slightly acidic fluid that constitutes about 25% of semen volume and contributes to sperm motility
• Bulbourethral glands

  • Secrete mucus for lubrication and an alkaline substance that neutralizes acid
• Semen

  Mixture of sperm and seminal fluid that provides fluid for sperm transport, nutrients, and neutralizes acidity

  
• Penis

  • Consists of root, body, and glans
  • Functions to introduce sperm into the vagina
  • Expansion of blood sinuses causes erection
• Scrotum

  • Sac that supports and regulates the temperature of the testes
• Seminiferous tubules

  • Where sperm cells develop

  
• Sustenacular cells

  • Nourish sperm cells and produce inhibin
• Interstitial cells

  • Produce testosterone

  
• Spermatogenesis

  1. Meiosis I

  2. Meiosis II

  3. Spermiogenesis

  
• Sperm cell

  • Consists of head and tail
  • Function is to fertilize a secondary oocyte

  
• Gonadotropin-releasing hormone (GnRH)

  Stimulates anterior pituitary secretion of LH and FSH
• Luteinizing hormone (LH)


  Stimulates interstitial cells to produce testosterone

  
• Follicle stimulating hormone (FSH)


  Initiates spermatogenesis
• Testosterone

  • Controls growth, development, and maintenance of sex organs
  • Stimulates bone growth, protein anabolism, and sperm maturation
  • Stimulates development of male secondary sex characteristics

  
• Inhibin


  • Produced by sustenacular cells
  • Helps regulate the rate of spermatogenesis
• Impotence may result from certain drugs, alcohol consumption, and emotional distress
• Viagra

  Causes the release of nitric oxide, which relaxes smooth muscle in arteries of the penis, allowing blood to enter and cause erection
• Overexpression of DHT can lead to male pattern baldness
• Female reproductive system


  • Includes vulva, vagina, uterus, fallopian tubes, and ovaries
  • Functions are to produce ova, transport ova, provide a site for fertilization and embryo development, and produce female sex hormones

  
• Ovaries


  • Produce secondary oocytes
  • Discharge secondary oocytes (ovulation)
  • Secrete estrogen and progesterone

  
• Oogenesis


  1. Includes meiosis I and meiosis II

  2. Completed only after fertilization of ovulated secondary oocyte
• Fallopian tube


  Transports secondary oocyte from ovary to uterus, normal site of fertilization
• Uterus

  • Functions in menstruation, implantation of fertilized ovum, and development of embryo/fetus

  
• Ovaries


  Located in the upper pelvic cavity on either side of the uterus
• Ovaries


  • Produce secondary oocytes
  • Discharge secondary oocytes (the process of ovulation)
  • Secrete
• Oogenesis


  1. Meiosis I

  2. Meiosis II
• Oogenesis sequence is completed only after an ovulated secondary oocyte is fertilized by a sperm cell

  
• Uterine tube


  Transports a secondary oocyte from an ovary to the uterus, is the normal site of fertilization
• Uterus

  An organ the size and shape of an inverted pear that functions in menstruation, implantation of a fertilized ovum, development of a fetus during pregnancy, and labor. It also is part of the pathway for sperm to reach a uterine tube to fertilize a secondary oocyte

  
• Endometrium


  The innermost layer of the uterine wall that undergoes marked changes during the menstrual cycle
• Vagina

  A passageway for the menstrual flow, the receptacle for the penis during sexual intercourse, and the lower portion of the birth canal. The smooth muscle of the vaginal wall makes it capable of considerable stretching
• Components of the vulva

  • Mons pubis
  • Labia majora
  • Labia minora
  • Clitoris
  • Vestibule
  • Vaginal and urethral orifices
  • Paraurethral glands
  • Greater vestibular glands
• Mammary glands


  Modified sweat glands located over the pectoralis major muscles. Their function is to secrete and eject milk (lactation)