Development Vocabulary

  1. zona reaction
    fusion of sperm head acrosome with zona pellucida releasing enzymes that cause Ca2+ mediated release of cortical granules to make the egg impenetrable to subsequent sperm
  2. trophoblast
    pluripotent stem cells which will form the syncytiotrophoblast and cytotrophoblast that form the placenta
  3. compaction
    migration of inner cell mass to one pole of the embryo to form a fluid filled centre (blastocoel)
  4. hatching
    emergence of the embryo from the zona pellucida before implantation
  5. syncytiotrophoblast
    first penetrating cells of the placenta which also secrete HCG for the maintenance of the corpus luteum in the first trimester for progesterone secretion
  6. primary villi
    placental tissue penetrating into the endometrial stroma consisting of two layers: syncytiotrophoblast and cytotrophoblast
  7. secondary villi
    placental tissue penetrating into the endometrial stroma consisting of three layers: syncytiotrophoblast, cytotrophoblast and extraembryonic mesoderm
  8. decidual reaction
    differentiation of uterine endometrium to form layered structure that supports embryo
  9. decidua basalis
    outermost layer of endometrium (during pregnancy known as decidua) that surrounds the implanting embryo forming a strong cellular matrix that allows for controlled invasion; in contact with trophoblast cells
  10. cotelydons
    arrangement of chorion on maternal side
  11. chorion
    maternal side of placenta
  12. amnion
    fetal side of placenta, formed from migration of epiblast cells outwards
  13. yolk sac
    formed by migration of hypoblast outwards
  14. tertiary villi
    placental tissue penetrating into the endometrial stroma consisting of syncytiotrophoblast, cytotrophoblast, extraembryonic mesoderm and fetal capillaries (formed from extraembryonic mesoderm)
  15. chorion frondosum
    part of trophoblast that remains in contact with uterine wall forming the placenta proper
  16. chorion laeve
    part of trophoblast that fuses with the amniotic sac and decidua to form the outer covering of the amniotic cavity
  17. amniotic cavity
  18. gastrulation
    migration of epiblast cells during the third week into the primitive streak to form the mesoderm, forming a trilaminar disc of ectoderm (epiblast), mesoderm (migrated cells) and endoderm (hypoblast)
  19. products of endoderm
    GIT, respiratory tract
  20. products of ectoderm
    CNS, skin
  21. products of mesoderm
    genitourinary tract, skeletal muscle, bone, connective tissue
  22. embryonic folding
    looping of the trimlaminar disc, amnion and yolk sac to form a tubular structure at the end of the third weekImage Upload 1
Card Set
Development Vocabulary
embryogenesis new words