Chapter 15 – The Lung: Congenital Anomalies Flashcards
The lungs are ingeniously constructed to carry out their cardinal function:
the exchange of
gases between inspired air and blood
Developmentally, the respiratory system is an outgrowth
from the ______________
ventral wall of the foregut.
The midline trachea develops two lateral outpocketings, the
lung buds.
Which lung deveop with 3 branches?
The right lung bud eventually divides into three branches—the lobar bronchi—and
the left into two lobar bronchi,
thRee= RIGHT
How many branches does the left lung has?
TWO
lefT
Why are aspirated foreign materials, such as vomitus, blood, and foreign bodies, tend to
enter the right lung more than the left.
The right main stem bronchus is more vertical and more directly in line with the trachea.
Consequently, aspirated foreign materials, such as vomitus, blood, and foreign bodies, tend to
enter the right lung more than the left.
The lobar right and left bronchi branch _______,
giving rise to progressively smaller airways.
dichotomously
Describe the arterial supply of the lungs.
Accompanying the branching airways is the double
arterial supply to the lungs, that is, the pulmonary and bronchial arteries.
What is the order of branching towards the lungs?
- bronchi
- bronchioles
- terminal bronchioles
- acinus
- respiratory bronchioles
- alveolar ducts and
- alveolar sacs
Differentiatebronchi forms bronchioles
which are distinguished from bronchi
by the lack of cartilage and submucosal glands within their walls.
Further branching of
bronchioles leads to the____________
terminal bronchioles, which are less than 2 mm in diameter
What is an acinus?
The part of
the lung distal to the terminal bronchioleis called the acinus; it isroughly spherical, with a
diameter of about 7 mm.
An acinus is composed of :
- respiratory bronchioles (which give off several alveoli from their sides),
- alveolar ducts,
- and alveolar sacs
What are alveolar sacs?
alveolar sacs, the blind ends of the
respiratory passages, whose walls are formed entirely of alveoli, which are the site of gas
exchange.
Whta is a pulmonary lobule?
A cluster of three to five terminal bronchioles, each with its appended acinus, is
referred to as the pulmonary lobule.
This lobular architecture assumes importance in
distinguishing the major forms of emphysema
What is the lining epithelium of the respiratory tree?
Except for the vocal cords, which are covered by stratified squamous epithelium, the entire
respiratory tree, including the larynx, trachea, and bronchioles, is lined by pseudostratified, tall,
columnar, ciliated epithelial cells.
What can you find the the bronchial mucosa?
The bronchial mucosa also contains a population of
neuroendocrine cells that have neurosecretory-type granules and can release a variety of
factors, including serotonin, calcitonin, and gastrin-releasing peptide (bombesin).
Numerous
mucus-secreting goblet cells and submucosal glands are dispersed throughout the walls of the
trachea and bronchi (but not the bronchioles).