FETAL LUNG DEVELOPMENT
TEST BANK Q & A
Fetal Lung Development Test Bank
1. Which of the following phases of human lung development is characterized by the formation
of a capillary network around airway passages?
a.
Pseudoglandular
b.
Saccular
c.
Alveolar
d.
Canalicular
ANS: D
The canalicular phase follows the pseudoglandular phase, lasting from approximately 17
weeks to 26 weeks of gestation. This phase is so named because of the appearance of
vascular channels, or capillaries, which begin to grow by forming a capillary network around
the air passages. During the pseudoglandular stage, which begins at day 52 and extends to
week 16 of gestation, the airway system subdivides extensively and the conducting airway
system develops, ending with the terminal bronchioles. The saccular stage of development,
which takes place from weeks 29 to 36 of gestation, is characterized by the development of
sacs that later become alveoli. During the saccular phase, a tremendous increase in the
potential gas- exchanging surface area occurs. The distinction between the saccular stage and
the alveolar stage is arbitrary. The alveolar stage stretches from 39 weeks of gestation to
term. This stage is represented by the establishment of alveoli.
2. Regarding postnatal lung growth, by approximately what age do most of the alveoli that will
be present in the lungs for life develop?
a.
6 months
b.
1 year
c.
1.5 years
d.
2 years
, FETAL LUNG DEVELOPMENT
TEST BANK Q & A
ANS: C
Most of the postnatal formation of alveoli in the infant occurs over the first 1.5 years of life.
At 2 years of age, the number of alveoli varies substantially among individuals. After 2 years
of age, males have more alveoli than do females. After alveolar multiplication ends, the
alveoli continue to increase in size until thoracic growth is completed.
3. The respiratory therapist is evaluating a newborn with mild respiratory distress due to tracheal
stenosis. During which period of lung development did this problem develop?
TEST BANK Q & A
Fetal Lung Development Test Bank
1. Which of the following phases of human lung development is characterized by the formation
of a capillary network around airway passages?
a.
Pseudoglandular
b.
Saccular
c.
Alveolar
d.
Canalicular
ANS: D
The canalicular phase follows the pseudoglandular phase, lasting from approximately 17
weeks to 26 weeks of gestation. This phase is so named because of the appearance of
vascular channels, or capillaries, which begin to grow by forming a capillary network around
the air passages. During the pseudoglandular stage, which begins at day 52 and extends to
week 16 of gestation, the airway system subdivides extensively and the conducting airway
system develops, ending with the terminal bronchioles. The saccular stage of development,
which takes place from weeks 29 to 36 of gestation, is characterized by the development of
sacs that later become alveoli. During the saccular phase, a tremendous increase in the
potential gas- exchanging surface area occurs. The distinction between the saccular stage and
the alveolar stage is arbitrary. The alveolar stage stretches from 39 weeks of gestation to
term. This stage is represented by the establishment of alveoli.
2. Regarding postnatal lung growth, by approximately what age do most of the alveoli that will
be present in the lungs for life develop?
a.
6 months
b.
1 year
c.
1.5 years
d.
2 years
, FETAL LUNG DEVELOPMENT
TEST BANK Q & A
ANS: C
Most of the postnatal formation of alveoli in the infant occurs over the first 1.5 years of life.
At 2 years of age, the number of alveoli varies substantially among individuals. After 2 years
of age, males have more alveoli than do females. After alveolar multiplication ends, the
alveoli continue to increase in size until thoracic growth is completed.
3. The respiratory therapist is evaluating a newborn with mild respiratory distress due to tracheal
stenosis. During which period of lung development did this problem develop?
