During which phase of fetal development do mature alveoli appear? ...

[Sportsfan2111]

During which phase of fetal development do mature alveoli appear?
 
  a. Alveolar
  b. Canalicular
  c. Pseudoglandular
  d. Saccular

Question 2

By which of the following routes does blood flow through the umbilical cord between the pla-centa and the fetus?
 
  a. One umbilical vein and one umbilical ar-tery
  b. One umbilical vein and two umbilical ar-teries
  c. Two umbilical veins and one umbilical ar-tery
  d. Two umbilical veins and two umbilical arteries

[tuwy]

Answer to Question 1

ANS: A
The development of mature alveoli, accompanied by capillary proliferation within the walls, marks the final phase of lung development and is known as the alveolar period.

Answer to Question 2

ANS: B
Maternal blood flows into the intervillous space through the spiral arteries, while fetal blood is supplied to the villi from two umbilical arteries. Oxygenated fetal blood leaves the chorionic villi capillaries through placental venules and returns to the fetus through a single umbilical vein.