ch 14 pt 3

• implantation


  when the embryo attatches to the uterus and burrows inside the uterine epithelium, remodeling the uterine blood supply and forming the placenta
• which 2 proteins does the endometrium express in order for the blastocyst to be "caught"

  selectin & integrin proteins
• 4 functions of the human embryo

  1. ovulation of the oocyte
  2. ease the sperm as it travels through the cervix
  3. ability of the uterus to attach and support growth of embryo
  4. repression of the mother's immune response against the embryo
• 2 layers of the uterus, what is unique about the human uterus in comparison to other mammals?

  Endometrium and myometrium; the human uterus is a regenerating organ
• during apposition where is mucin-1 expressed? what else is expressed here?

  1. epithelial cells
  2. ligands for L-selectin
• during the adhesion section what is the role of leukemia inhibitory factor (LIF) in adhesion?


  helps attract the embryo to the regions of the uterus where adhesion can be the strongest
• during the adhesion stage why and how do trophoblast cells "disguise their identity?" 


  trophoblast cells form anchoring sites that firmly connect the embryo to the uterus and they disguise their identity to avoid being attacked by the mothers immune system
• during the progression stage how do the original cells differ from the new cells and what are the names of these layers?


  the original trophoblast cells create the cytotrophoblast and the multinucleated cell type forms the syncytiotrophoblast
• during the decidualization stage what is the "centerpiece" of decidualization


  transformation of the fibroblast like stromal cells lining the uterus to become the secretory uterine decidual cells
• during the decidualization stage what do the uterine decidual cells induce and why is it important?


  differentiation of uterine NK cells that are involved in suppressing the mothers immune system
• during the decidualization stage what could happen if decidualization was not a local phenomenon?


  it would spread through the entire uterus and endanger the mother
• what has classically been considered one of the greatest threats to normal pregnancy

  inflammation
• why is the embryo considered to be a foreign object

  it has maternal and paternal proteins on its surface
• why do some scientists believe that implantation in some early mammalian species triggered the full inflammatory response?

  marsupial pregnancies have a very short period of maternal-fetal attatchment
• what is a eutherian mammal and what happens that enables the uterus to retain the embryo

  blocking 2 of the 5 inflammatory pathways enable the uterus to retain the embryo
• what is the role of fetal lungs in ending pregnancy

  the lung surfactants enter the amnion activating macrophages in the amniotic fluid where they secrete proteins that initiate inflammatory response that help go into labor
• how does the fetus and uterus use the maternal immune system to both begin and end pregnancy

  when the lungs have matured (so the newborn can take its first breath) that signal is transmitted to the mother via her immune system to end pregnancy. to begin pregnancy the maternal immune system shuts down for implantation