SCIENCE: FEMALE REPRODUCTIVE SYSTEM

• Reproduction is the process in which an organism produces offspring
• Reproduction is one of the characteristics of life and a reason why organisms survive
• There are 2 ways living things reproduce: Sexual and Asexual
• Sexual reproduction involves 2 parents or a partner and the union of 2 nuclei to form a sex cell
• Sexual reproduction uses gametes (sex cells) produced by females (egg cells) and males (sperm cells) that combine to produce unique offspring
• Genetic recombination ensures that offspring are not exact copies of their parents
• Asexual reproduction only requires 1 parent and does not involve reproductive cells
• Asexual reproduction results in clones or copies where the genetic material of the parent is the same as the offspring
• Budding is a form of asexual reproduction where an outgrowth leads to the separation of the original organism into two individuals
• Binary fission is a form of asexual reproduction that happens in bacteria
• Female reproductive system organs are for intercourse, reproduction, urination, pregnancy, and childbirth
• Internal female parts include the ovary, fallopian tubes, uterus, cervix, vagina, urethra, and clitoris
• Ovary:

  • Two solid egg-shaped structures attached to the uterus by ligaments
  • Store and release ova (female egg cells) and produce female sex hormones estrogen and progesterone
• Ova:

  • Female reproductive cells, the largest cells in the female body
  • Female babies are born with all the ova they will ever have, about 200,000 in each ovary
  • About 400 to 500 ova mature and are released over a lifetime
• Estrogen:

  • Responsible for secondary sex characteristics, sex drive, onset of puberty, and ovulation
• Progesterone:

  • Builds up the lining of the uterus (endometrium) in preparation for a fertilized ovum
• Fallopian Tubes:

  • Two tubes attached to either side of the uterus, carrying egg cells toward the uterus and sperm cells toward the egg cell
  • Site of fertilization
• Uterus:

  • Hollow muscular organ lined with endometrium, protecting and nourishing a fetus
  • Walls can stretch to the size of a small watermelon and shrink back after childbirth
• Cervix:

  • The neck or opening of the uterus, strongest muscle in the body
  • Dilates for childbirth depending on the size of the baby
• Vagina:

  • Female organ for intercourse, passageway from vaginal opening to the uterus
  • Walls stretch to accommodate a baby during birth and secrete fluid to aid intercourse
• Urethra:

  • Opening to the bladder
• Clitoris:

  • Small bump at the front of the labia containing erectile tissue, increasing sexual pleasure
• Woman's Cycle:

  Day 1: Menstruation begins bleeding

  Day 5: Menstruation usually ends

  Day 14: Ovum matures and bursts out of the ovary

  Day 15: Egg is released

  Day 26: In the absence of fertilization, estrogen/progesterone levels drop and the endometrium lining breaks down

  Day 28: Menstruation begins again
• TIMELINE:

  Ages:

  • 9-12: Secondary sex characteristics appear
  • 11-14: Menstrual cycle begins
  • 20-30's: Peak sexual urges
  • 45-55: Menopause, where both the ovarian and menstrual cycles stop, but sexual urges continue