12.The primitive uteroplacental circulation is functionally established
during which period of embryonic/fetal development?
a. First week
b. Second week
c. Third week
d. End of first month
e. Second trimester
13.The ectoderm is derived directly from which of the following?
a. Hypoblast
b. Epiblastic cells that undergo gastrulation
c. Mesoderm
d. Endoderm
e. Nongastrulated epiblast
14.Fetal blood from the placenta is about 80% oxygenated. However, mix-
ture with unoxygenated blood at various points reduces the oxygen content.
Which of the following fetal vessels contains blood with the highest oxygen
content?
a. Abdominal aorta
b. Common carotid arteries
c. Ductus arteriosus
d. Pulmonary artery
e. Pulmonary vein
Embryology: Early and General 75