Practice Quiz - Second Week (Days 8-14)

  1. The completion of interstitial implantation, so that the conceptus is entirely within the endometrium, occurs:
    on about day 20
    by about day 11
    by the end of the first week
    by erosion of the myometrial lining
    as a result of endodermal proliferation
  2. Both the neurenteric canal and the notochordal plate are present in the conceptus at the same time.
    true
    false
  3. The amniotic cavity develops:
    on the tenth day
    within the outer cell mass
    within the inner cell mass near the cytotrophoblast
    in extraembryonic mesoderm
    none of the above
  4. During the second week of development, the trophoblast differentiates into:
    syncytiotrophoblast
    ectoderm
    intraembryonic mesoderm
    yolk sac (secondary)
  5. Major events beginning in the second week of development include:
    notochord differentiation
    somite formation
    angiogenesis
    yolk sac development
  6. The first two intraembryonic germ layers to differentiate are the:
    ectoderm & hypoblast
    epiblast & hypoblast
    ectoderm & endoderm
    ectoderm & mesoderm
  7. The blastocoele becomes the:
    amniotic cavity
    extraembryonic coelom
    primary yolk sac
    chorionic cavity
    secondary cavity
  8. Extraembryonic somatic mesoderm is in close association with:
    syncytiotrophoblast
    cytotrophoblast & amnion
    yolk sac
    syncytio- & cytotrophoblast
  9. Cytotrophoblast cells become:
    secondary yolk sac
    amnioblasts
    exocoelomic membrane
    syncytiotrophoblast
  10. The yolk sac in the human embryo:
    does not contribute to the embryonic gut
    is devoid of hemopoietic activity, or blood cell formation
    is the site of primordial germ cell production
    stores nutrients throughout pregnancy
  11. The bilaminar germ disc:
    consists of epiblast and mesoblast
    is derived from the outer cells of the morula
    forms the embryo proper
    synthesizes human chorionic gonadotropin, HCG
  12. The definitive yolk sac of the embryo appears by what day?
    13th
    26th
    72nd
    94th
    2nd
  13. The amniotic cavity appears as a slit-like space near the embryonic polar trophoblast and within the:
    extraembryonic mesoderm
    exocoelomic membrane
    inner cell mass
    connecting body stalk
    cytotrophoblast
  14. During the second week, the embryonic disk is composed of:
    ectoderm
    ectoderm and mesoderm
    endoderm
    epiblast and hypoblast
    ectoderm, mesoderm and endoderm
  15. The part of the 13-day embryoblast from which the embryo proper is formed:
    lies between the amniotic cavity and yolk sac
    also contributes to the roof of the yolk sac
    is composed of two primary germ layers
    is attached to the amnion
    all of the above are correct
  16. The cloacal membrane consists of:
    embryonic endoderm, mesoderm and ectoderm
    endoderm of the roof of the yolk sac and embryonic ectoderm
    a spherical area of endoderm fused to embryonic mesoderm
    the prochordal plate and the overlying embryonic endoderm
    none of the above
  17. The amniotic cavity develops:
    on the 10th day
    within the inner cell mass
    between inner cell mass and trophoblast
    in the extraembryonic mesoderm
    between two layers of cytotrophoblast
  18. Which statement about the 14-day blastocyst is NOT true?
    villi are absent
    extraembryonic coelom surrounds the yolk sac
    primitive uteroplacental circulation is established
    extraembryonic mesoderm is split into two layers
    none of the above
  19. The ___________ gives rise to the extraembryonic mesoderm.
    ectoderm
    hypoblast
    blastocyst
    trophoblast
    syncytiotrophoblast
    cytotrophoblast
    blastocoele
    inner cell mass
    notochord
    prochordal plate
    primary yolk sac
    amniotic cavity
    intraembryonic coelom
    secondary yolk sac
  20. Which layer of the bilaminar embryonic disc forms part of the lining of the amniotic cavity?
    epiblast
    hypoblast
    blastocyst
    trophoblast
    syncytiotrophoblast
    cytotrophoblast
    blastocoele
    inner cell mass
    notochord
    prochordal plate
    primary yolk sac
    amnioblast
    intraembryonic coelom
    secondary yolk sac
  21. Which layer invades into the maternal endometrium and forms the lacunar network for placental-maternal exchange?
    blastocyst
    cytotrophoblast
    syncytiotrophoblast
    endoderm
    ectoderm
    mesoderm
  22. Which layer is acellular, does not expand mitotically, and produces human chorionic gonadotropin (hCG) which stimulates progesterone production by the corpus luteum?
    syncytiotrophoblast
    cytotrophoblast
    epiblast
    endoderm
    ectoderm
    mesoderm
  23. Which layer is cellular and expands mitotically into syncytiotrophoblast to form primary chorionic villi that can be used in chorionic villus sampling or genetic testing for the early fetus?
    syncytiotrophoblast
    cytotrophoblast
    epiblast
    endoderm
    ectoderm
    mesoderm
  24. What malignant tumor arises from trophoblastic cells?
    Liposarcoma
    Rhabdomyosarcoma
    Fibroma
    Choriocarcinoma
    Endometrioma
  25. How does a hydatidiform mole occur?
    Hyperplastic proliferation of trophoblast within the uterine wall
    Malignant transformation of endometrial cells
    Malignant transformation of ovarian cells
    Malignant proliferation of blastocyst