Practice Quiz - Development of the Placenta and Extraembryonic Membranes
  1. The umbilical cord may loop around the fetus or become knotted, which may cause fetal distress.
    true
    false
  2. When the amount of amniotic fluid exceeds two liters, the condition is called:
    oligohydramnios
    polyhydramnios or hydramnios
    amniotitis
    bag of waters
    hydrogravida
  3. The wall of the chorionic sac is composed of:
    cytotrophoblast and syncytiotrophoblast
    two layers of trophoblast lined by extraembryonic somatic mesoderm
    trophoblast and exocoelomic membrane
    extraembryonic splanchnic mesoderm & both layers of trophoblast
    none of the above
  4. The most distinctive characteristic of a primary chorionic villus is its:
    outer syncytiotrophoblastic layer
    cytotrophoblastic shell
    extraembryonic somatic mesodermal core
    bushy appearance
    cytotrophoblastic core
  5. Chorionic villi are designated as secondary chorionic villi when they:
    contact the decidua basalis
    are covered by syncytiotrophoblast
    develop a mesenchymal core
    give rise to branch villi
    none of the above
  6. When chorionic villi become vascularized they are called ____ villi.
    branch
    stem
    tertiary
    anchoring
    mature
  7. The most important region of the decidua for the nourishment of the conceptus is the decidua _______.
    frondosum
    capsularis
    parietalis
    basalis
    laeve
  8. The intervillous space contains all of the following substances EXCEPT:
    oxygen
    carbon dioxide
    maternal blood cells
    fetal blood
    electrolytes
  9. Which of the following materials usually do not cross the placental membrane or barrier?
    free fatty acids
    steroid hormones
    bacteria
    vitamins
    viruses
  10. The tissue of the four-week embryo that lies in contact with the decidua basalis is:
    cytotrophoblast shell
    syncytiotrophoblast villi
    chorion laeve
    extraembryonic somatic mesoderm
    all of the above
  11. At or near term, the intervillous space has a total volume of:
    150 ml
    400 ml
    500 ml
    1000 ml
    1500-2000 ml
  12. The primary source of fetal energy is:
    the fetal intestines
    the placenta
    amniotic fluid
    maternal fat
  13. The portion of the decidua which does not survive until the end of pregnancy is the:
    capsularis
    basalis
    laeve
    parietalis
    frondosum
  14. Attachment of the umbilical cord to the fetal membranes instead of to the placenta is called:
    battledore placenta
    Wharton's placenta
    velamentous insertion
    cotyledon placenta
    eccentric insertion
  15. Amniotic fluid IS NOT concerned with:
    regulation of fetal temperature
    exchange of fetal wastes
    protection of the conceptus
    early nutrition of the embryo
  16. Which of the following is NOT true concerning decidua basalis:
    lies between the villous chorion and the myometrium
    forms the "roof" of the placenta
    supplies blood to the intervillous spaces
    is partially composed of fetal tissues
  17. Mechanisms involved in placental transfer of material include:
    facilitated diffusion
    pinocytosis
    active transport
    simple diffusion
    all of the above are correct
  18. Which of the following is NOT true concerning the umbilical cord?
    it usually attaches near the center of the placenta
    it may not be attached to the placenta
    it normally contains two arteries and one vein
    it may form a knot that can cause fetal distress
    it contains cardiac jelly
  19. The chorionic sac surrounds the embryo, amniotic sac and yolk sac.
    true
    false
  20. Which of the following is NOT a component of the mature placental barrier?
    the endothelial lining of fetal capillaries
    the cytotrophoblast
    the syncytiotrophoblast
    the basement membrane of fetal capillaries
    all of the above are part of the mature placental barrier
  21. Which is NOT true concerning the human placenta:
    is divided into a number of cup-like compartments by incomplete septae of maternal tissue
    has an intervillous space filled with maternal blood and lined by syncytiotrophoblast
    has chorionic villi as functional units
    is anchored to maternal tissue by columns of syncytiotrophoblast
  22. In placenta praevia, the placenta may detach and cause severe bleeding and fetal anoxia during delivery.
    true
    false
  23. The human placenta:
    has a maternal component formed by the decidua capsularis
    shows no changes with age
    retains the cytotrophoblast layer of the placental barrier throughout gestation
    has chorionic villi as the structural and functional unit
  24. The placental intervillous space:
    is divided into compartments by the placental septa
    is a continuous space throughout the placenta
    is lined by syncytiotrophoblast
    contains circulating maternal blood
    all of the above are correct
  25. Under normal conditions, the placenta acts as a barrier against:
    transfer of drugs and their metabolites
    transfer of all infectious agents
    transfer of nutrients
    mixing of maternal and fetal blood
    transfer of hormones
  26. Human chorionic gonadotropin (HCG) is produced by the:
    syncytiotrophoblast
    anterior pituitary gland
    theca folliculi
    corpus luteum of pregnancy
    embryoblast
  27. Which of the following materials usually cross the placental membrane?
    free fatty acids
    steroid hormones
    drugs and chemicals with a molecular weight of less than 500
    vitamins
    all of the above
  28. Which structure is responsible for transport of nutrients to the fetus?
    cytotrophoblastic shell
    trophoblast
    decidua basalis
    cotyledon
    spiral artery
    intervillous space
    tertiary villus
    umbilical artery
    umbilical vein
    syncytial knots
    vitelline duct
    chorion frondosum
    amnion
  29. Which structure is found in the umbilical cord, but is not part of the fetal circulatory system?
    cytotrophoblastic shell
    trophoblast
    decidua basalis
    cotyledon
    spiral artery
    intervillous space
    tertiary villus
    umbilical artery
    umbilical vein
    syncytial knots
    vitelline duct
    chorion frondosum
    amnion
  30. Which of the following structures should normally be found as a pair?
    cytotrophoblastic shell
    trophoblast
    decidua basalis
    cotyledon
    spiral artery
    intervillous space
    tertiary villus
    umbilical artery
    umbilical vein
    syncytial knot
    vitelline duct
    chorion frondosum
    amnion
  31. What is the maternal and fetal portions of the placenta respectively?
    villous chorion / decidua basalis
    decidua basalis / villous chorion
    anchoring villi / cytotrophoblastic shell
  32. Which poisonous gas can cross the placental membrane?
    carbon monoxide
    oxygen
    carbon dioxide
    methyldopa
  33. There are three circulatory shunts in fetal circulation. Which one allows blood from the placenta to bypass the liver?
    ductus arteriosus
    foramen ovale
    ductus venosus
    foramen seccundum
    arteriovenous fistula
  34. Erythroblastosis fetalis occurs due to what?
    AB incompatibility
    Rh+ baby born to Rh- mother
    In utero Rubella infection
    In utero HIV infection
  35. What abnormality causes oligohydramnios?
    POTTER sequence
    esophageal atresia
    anular pancreas
    microcephaly
    renal agenesis