, Walsh: Perinatal and Pediatric Respiratory Care, 3rd Edition
Chapter 1: Fetal Lung Development
Test Bank
MULTIPLE CHOICE
1. Which of the following phases of human lung development occurs from 17 to 26 weeks of
gestation, and is characterized by the formation of a capillary network around airway passages?
A. Pseudoglandular
B. Saccular
C. Alveolar
D. Canalicular
ANS: D
Feedback
A. Incorrect response: The pseudoglandular stage occurs from day 52 and extends to
week 16 of gestation, and features extensive subdivision of the airway system, as
well as the development of the conducting airway system ending with the
terminal bronchioles.
B. Incorrect response: The saccular stage of development takes place during weeks
29 to 36 of gestation, and 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.
C. Incorrect response: 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.
D. Correct response: The canalicular stage extends from about 17 to 26 weeks of
gestation. Vascular channels, or capillaries, appear and approximate the air
passages, forming a capillary network around them.
OBJ: Recall
NOT: The stage that has not been mentioned here is the embryonal stage, occurring from day
16 to day 52, during which time the trachea and major bronchi form.
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
ANS: C
A. Incorrect response: See explanation C.
B. Incorrect response: See explanation C.
C. Correct response: Most of the postnatal formation of alveoli in the infant occurs
over the first 1.5 years of life.
D. Incorrect response: See explanation C.
OBJ: Recall
3. Which of the following mechanisms appear to explain why oligohydramnios is associated with
lung hypoplasia?
I. Abnormal carbohydrate metabolism
II. Mechanical restriction of the chest wall
III. Interference with fetal breathing
IV. Failure to produce fetal lung liquid
A. I and III only
B. II and III only
C. I, II, and IV only
D. II, III, and IV only
ANS: D
Feedback
A. Incorrect response: Leprechaunism, associated with abnormal carbohydrate
metabolism, results in dysmorphic lungs with a decreased number of terminal
bronchioles, dilated alveolar ducts and saccules, and enlarged airspaces.
B. Incorrect response: See explanation D.
C. Incorrect response: See explanation D.
D. Correct response: Oligohydramnios, reduced amniotic fluid for an extended
period, with or without renal anomalies, is associated with lung hypoplasia.
Possible mechanisms responsible for the association between reduced amniotic
fluid and lung hypoplasia include mechanical restriction of the chest wall,
interference with fetal breathing, and failure to produce fetal lung liquid.
OBJ: Recall
4. What is the purpose of the material secreted by the type II pneumocyte?
A. To increase the gas exchange surface area
B. To reduce surface tension
C. To maintain lung elasticity
D. To preserve the volume of the amniotic fluid
ANS: B
Feedback
A. Incorrect response: See explanation B.
B. Correct response: The alveolar epithelial lining is composed of type I and II
pneumocytes. The type I pneumocytes are squamous cells serving as a thin, gas-
permeable membrane and account for more than 97% of the alveolar surface
area. The cuboidal-appearing type II pneumocyte is the pulmonary surfactant–
producing cell. Pulmonary surfactant reduces the surface tension of the alveolar
lining layer at the air–liquid interface. In addition, type II pneumocytes are
involved with surfactant storage, secretion, and reuptake.
C. Incorrect response: See explanation B.
D. Incorrect response: See explanation B.
OBJ: Recall
5. Which of the following vascular networks is the major source of fetal lung liquid?
A. Pulmonary circulation
B. Pulmonary lymphatics
C. Systemic circulation
D. Bronchial circulation
ANS: A
Feedback
A. Correct response: The pulmonary circulation is the major source of fetal lung
liquid. The balance between the production and drainage of this liquid has an
important effect on lung development. During fetal breathing, a small but steady
movement of fluid leaving the trachea occurs. The net movement of fluid from
the lungs has been measured as occurring at about 15 ml/hour and was about five
times higher during periods of fetal breathing than during apnea.
B. Incorrect response: See explanation A.
C. Incorrect response: See explanation A.
D. Incorrect response: See explanation A.
Stuvia customers have reviewed more than 700,000 summaries. This how you know that you are buying the best documents.
Quick and easy check-out
You can quickly pay through credit card for the summaries. There is no membership needed.
Focus on what matters
Your fellow students write the study notes themselves, which is why the documents are always reliable and up-to-date. This ensures you quickly get to the core!
Frequently asked questions
What do I get when I buy this document?
You get a PDF, available immediately after your purchase. The purchased document is accessible anytime, anywhere and indefinitely through your profile.
Satisfaction guarantee: how does it work?
Our satisfaction guarantee ensures that you always find a study document that suits you well. You fill out a form, and our customer service team takes care of the rest.
Who am I buying these notes from?
Stuvia is a marketplace, so you are not buying this document from us, but from seller ExamsExpert. Stuvia facilitates payment to the seller.
Will I be stuck with a subscription?
No, you only buy these notes for £20.49. You're not tied to anything after your purchase.
