, Chapter 1: Fetal Lung Development Test Bank x x x x x x
MULTIPLE CHOICE x
1. Which of the following phases of human lung development is characterized by the fo
x x x x x x x x x x x x x
rmation of a capillary network around airway passages?
x x x x x x x
a. Pseudoglandular
b. Saccular
c. Alveolar
d. Canalicular
ANS: D x
The canalicular phase follows the pseudoglandular phase, lasting from approximately 17 weeks to 2
x x x x x x x x x x x x x
6 weeks of gestation. This phase is so named because of the appearance of vascular channels, or capi
x x x x x x x x x x x x x x x x x
llaries, which begin to grow by forming a capillary network around the air passages.
x x x x x x x x x x x x x
During the pseudoglandular stage, which begins at day 52 and extends to week 16 of gestation, the a
x x x x x x x x x x x x x x x x x
irway system subdivides extensively and the conducting airway system develops, ending with the te
x x x x x x x x x x x x x
rminal bronchioles. The saccular stage of development, which takes place from weeks 29 to 36 of ge
x x x x x x x x x x x x x x x x
station, is characterized by the development of sacs that later become alveoli.
x x x x x x x x x x x
During the saccular phase, a tremendous increase in the potential gas-
x x x x x x x x x x
xexchanging surface area occurs. The distinction between the saccular stage and the alveolar stage is
x x x x x x x x x x x x x x
xarbitrary. The alveolar stage stretches from 39 weeks of gestation to term. This stage is represented
x x x x x x x x x x x x x x x x
by the establishment of alveoli.
x x x x
REF: pp. 3-5 x x
2. Regarding postnatal lung growth, by approximately what age do most of the alveoli that wi
x x x x x x x x x x x x x x
ll be present in the lungs for life develop?
x x x x x x x x
a. 6 months
x
,b. 1 year x
c. 1.5 years x
d. 2 years x
ANS: C x
Most of the postnatal formation of alveoli in the infant occurs over the first 1.5 years of life. At 2 year
x x x x x x x x x x x x x x x x x x x x
s of age, the number of alveoli varies substantially among individuals. After 2 years of age, males ha
x x x x x x x x x x x x x x x x x
ve more alveoli than do females. After alveolar multiplication ends, the alveoli continue to increase i
x x x x x x x x x x x x x x x
n size until thoracic growth is completed.
x x x x x x
REF: p. 6 x x
3. The respiratory therapist is evaluating a newborn with mild respiratory distress due to tr
x x x x x x x x x x x x x
acheal stenosis. During which period of lung development did this problem develop?
x x x x x x x x x x x
a. Embryonal
b. Saccular
c. Canalicular
d. Alveolar
ANS: A x
The initial structures of the pulmonary tree develop during the embryonal stage. Errors in developmen
x x x x x x x x x x x x x x
t during this time may result in laryngeal, tracheal, or esophageal atresia or stenosis. Pulmonary hypop
x x x x x x x x x x x x x x x
lasia, an incomplete development of the lungs characterized by an abnormally low number and/or size
x x x x x x x x x x x x x x
xof bronchopulmonary segments and/or alveoli, can develop during the pseudoglandular phase. If the f
x x x x x x x x x x x x x
etus is born during the canalicular phase (i.e., prematurely), severe respiratory distress can be expecte
x x x x x x x x x x x x x x
d because the inadequately developed airways, along with insufficient and immature surfactant produ
x x x x x x x x x x x x
ction by alveolar type II cells, gives rise to the constellation of problems known as infant respiratory di
x x x x x x x x x x x x x x x x x
stress syndrome. x
, REF: p. 6 x x
4. Which of the following mechanisms is (are) responsible for the possible association be
x x x x x x x x x x x x
tween oligohydramnios and lung hypoplasia?
x x x x
I. Abnormal carbohydrate metabolism x x
II. Mechanical restriction of the chest wall x x x x x
III. Interference with fetal breathing x x x
IV. Failure to produce fetal lung liquid
x x x x x
a. I and III only
x x x
b. II and III only
x x x
c. I, II, and IV only
x x x x
d. II, III, and IV only
x x x x
ANS: D x
Oligohydramnios, a reduced quantity of amniotic fluid present for an extended period of time, with
x x x x x x x x x x x x x x x
or without renal anomalies, is associated with lung hypoplasia. The mechanisms by which amniotic
x x x x x x x x x x x x x x
fluid volume influences lung growth remain unclear. Possible explanations for reduced quantity of a
x x x x x x x x x x x x x
mniotic fluid include mechanical restriction of the chest wall, interference with fetal breathing, or fai
x x x x x x x x x x x x x x
lure to produce fetal lung liquid. These clinical and experimental observations possibly point to a co
x x x x x x x x x x x x x x x
mmon denominator, lung stretch, as being a major growth stimulant.
x x x x x x x x x
REF: pp. 6-7 x x
5. What is the purpose of the substance secreted by the type II pneumocyte?
x x x x x x x x x x x x
MULTIPLE CHOICE x
1. Which of the following phases of human lung development is characterized by the fo
x x x x x x x x x x x x x
rmation of a capillary network around airway passages?
x x x x x x x
a. Pseudoglandular
b. Saccular
c. Alveolar
d. Canalicular
ANS: D x
The canalicular phase follows the pseudoglandular phase, lasting from approximately 17 weeks to 2
x x x x x x x x x x x x x
6 weeks of gestation. This phase is so named because of the appearance of vascular channels, or capi
x x x x x x x x x x x x x x x x x
llaries, which begin to grow by forming a capillary network around the air passages.
x x x x x x x x x x x x x
During the pseudoglandular stage, which begins at day 52 and extends to week 16 of gestation, the a
x x x x x x x x x x x x x x x x x
irway system subdivides extensively and the conducting airway system develops, ending with the te
x x x x x x x x x x x x x
rminal bronchioles. The saccular stage of development, which takes place from weeks 29 to 36 of ge
x x x x x x x x x x x x x x x x
station, is characterized by the development of sacs that later become alveoli.
x x x x x x x x x x x
During the saccular phase, a tremendous increase in the potential gas-
x x x x x x x x x x
xexchanging surface area occurs. The distinction between the saccular stage and the alveolar stage is
x x x x x x x x x x x x x x
xarbitrary. The alveolar stage stretches from 39 weeks of gestation to term. This stage is represented
x x x x x x x x x x x x x x x x
by the establishment of alveoli.
x x x x
REF: pp. 3-5 x x
2. Regarding postnatal lung growth, by approximately what age do most of the alveoli that wi
x x x x x x x x x x x x x x
ll be present in the lungs for life develop?
x x x x x x x x
a. 6 months
x
,b. 1 year x
c. 1.5 years x
d. 2 years x
ANS: C x
Most of the postnatal formation of alveoli in the infant occurs over the first 1.5 years of life. At 2 year
x x x x x x x x x x x x x x x x x x x x
s of age, the number of alveoli varies substantially among individuals. After 2 years of age, males ha
x x x x x x x x x x x x x x x x x
ve more alveoli than do females. After alveolar multiplication ends, the alveoli continue to increase i
x x x x x x x x x x x x x x x
n size until thoracic growth is completed.
x x x x x x
REF: p. 6 x x
3. The respiratory therapist is evaluating a newborn with mild respiratory distress due to tr
x x x x x x x x x x x x x
acheal stenosis. During which period of lung development did this problem develop?
x x x x x x x x x x x
a. Embryonal
b. Saccular
c. Canalicular
d. Alveolar
ANS: A x
The initial structures of the pulmonary tree develop during the embryonal stage. Errors in developmen
x x x x x x x x x x x x x x
t during this time may result in laryngeal, tracheal, or esophageal atresia or stenosis. Pulmonary hypop
x x x x x x x x x x x x x x x
lasia, an incomplete development of the lungs characterized by an abnormally low number and/or size
x x x x x x x x x x x x x x
xof bronchopulmonary segments and/or alveoli, can develop during the pseudoglandular phase. If the f
x x x x x x x x x x x x x
etus is born during the canalicular phase (i.e., prematurely), severe respiratory distress can be expecte
x x x x x x x x x x x x x x
d because the inadequately developed airways, along with insufficient and immature surfactant produ
x x x x x x x x x x x x
ction by alveolar type II cells, gives rise to the constellation of problems known as infant respiratory di
x x x x x x x x x x x x x x x x x
stress syndrome. x
, REF: p. 6 x x
4. Which of the following mechanisms is (are) responsible for the possible association be
x x x x x x x x x x x x
tween oligohydramnios and lung hypoplasia?
x x x x
I. Abnormal carbohydrate metabolism x x
II. Mechanical restriction of the chest wall x x x x x
III. Interference with fetal breathing x x x
IV. Failure to produce fetal lung liquid
x x x x x
a. I and III only
x x x
b. II and III only
x x x
c. I, II, and IV only
x x x x
d. II, III, and IV only
x x x x
ANS: D x
Oligohydramnios, a reduced quantity of amniotic fluid present for an extended period of time, with
x x x x x x x x x x x x x x x
or without renal anomalies, is associated with lung hypoplasia. The mechanisms by which amniotic
x x x x x x x x x x x x x x
fluid volume influences lung growth remain unclear. Possible explanations for reduced quantity of a
x x x x x x x x x x x x x
mniotic fluid include mechanical restriction of the chest wall, interference with fetal breathing, or fai
x x x x x x x x x x x x x x
lure to produce fetal lung liquid. These clinical and experimental observations possibly point to a co
x x x x x x x x x x x x x x x
mmon denominator, lung stretch, as being a major growth stimulant.
x x x x x x x x x
REF: pp. 6-7 x x
5. What is the purpose of the substance secreted by the type II pneumocyte?
x x x x x x x x x x x x
