human reproductive systems

• Hormone


  A chemical made in one body part that affects cells in another
• Target cells


  Cells that have receptors for particular hormones
• Gland


  An organ that produces and releases a substance or secretion, ie. Tear glands
• The purpose of human reproduction is to continue our species
• The testes are on the outside of a male because sperm present in male testes are not capable of surviving in the extreme heat of the inside of a human body
• Scrotum


  The sac that houses the testes
• Seminiferous tubules


  Where sperm cells develop within the testes
• Epididymis


  The place where mature sperm is stored
• Semen


  A compound consisting of a mix of sperm and seminal fluid
• Puberty


  A period of rapid physical and sexual maturation in humans
• Male secondary sex characteristics

  • Hair on face and chest
  • Pubic hair
  • Broad shoulders
  • Increased muscle development
  • Deeper voice
• Female secondary sex characteristics


  • Pubic hair
  • Armpit and leg hair
  • Breasts develop
  • Menstrual cycle
  • Weight gain on hips and posterior thighs
• Oviduct


  The tube through which an egg passes from an ovary
• Vagina


  A muscular canal that connects the uterus and cervix to the rest of the body
• Uterus


  The place where the fetus develops and grows
• Menstruation


  The body preparing itself for the nurturing of a fetus
• Menopause


  The permanent stopping of the menstrual cycle
• Fertilization


  When an sperm meets and penetrates the egg
• It takes several hundred sperm cells for sperm to fertilize an egg because sperm have to penetrate the egg's initial membrane, once penetrated, the sperm can fertilize the egg
• Zygote


  A fertilized egg
• Amniotic fluid


  A fluid that protects, cushions, and insulates the embryo
• Placenta


  The placenta is tissue that provides the fetus with oxygen and removes waste
• Umbilical cord


  The cord that connects a fetus to its mother
• Trimesters of pregnancy


  • First: All tissues, organs, and organ systems begin development
  • Second: Period of rapid growth, heartbeat is heard, bone replaces cartilage, hair begins to grow, and the mother can now feel the fetus move
  • Third: The fetus continues to grow rapidly, fat begins to accumulate, the organ systems mature, the fetus can now regulate its own body temp., the fetus now responds to sound
• Reasons for an ultrasound

  • To determine if the fetus is growing properly
  • To determine the position of the fetus
  • To determine the gender
• Labor


  When a female's water breaks, and the body is preparing itself for the delivery of an infant
• Oxytocin


  A hormone that stimulates the contraction of labor
• Prolactin


  The hormone that creates milk
• Stages of birth


  • Dilation: the dilation of the cervix
  • Expulsion: the mother will contract her abdominal muscles and push the baby out headfirst through the vagina
  • Placental: fetus detaches from the uterus and leaves the mother's body