Which six structures make up the conducting zone of the respiratory tree?
The nose, the pharynx, the trachea, the bronchi, the bronchioles, and the terminal bronchioles
Name the four functions of the conducting zone of the respiratory tree.
The conducting zone brings air in and out, warms, humidifies, and filters air
What type of muscle is found in the walls of the conducting airways?
What anatomic area does the respiratory zone encompass and what is the major function?
The respiratory bronchioles, the alveolar ducts, and the alveoli all function in gas exchange
Cartilage is present only in what two components of the respiratory tree?
Trachea and bronchi
Which zone of the respiratory tree includes the anatomic dead space?
The conducting zone; by definition, dead space does not participate in gas exchange
Goblet cells extend to the _____ (respiratory/terminal) bronchioles, whereas pseudostratified ciliated cells extend to the _____ (respiratory/terminal) bronchioles.
What type of pneumocyte makes up 97% of alveolar surfaces?
Type I pneumocytes
What type of pneumocyte makes up just 3% of pneumocytes?
Type II pneumocytes
What are two important functions of type II pneumocytes?
To secrete surfactant and to serve as precursors to pneumocytes (both types I and II)
What is dipalmitoyl phosphatidylcholine and what is its function?
Surfactant, to decrease alveolar surface tension
Which cells proliferate to repair the lungs after they have been damaged?
Type II pneumocytes; they are the precursors of both types of pneumocytes
What feature of the pseudostratified columnar cells of the respiratory tract allow them to move mucus toward the mouth?
What ratio of concentrations of which two molecules in amniotic fluid can be used as a marker of fetal lung maturity?
The lecithin/sphingomyelin ratio
A lecithin/sphingomyelin ratio with what value is indicative of fetal lung maturity?
Histologically, while type I pneumocytes are _____ (cuboidal/squamous), type II pneumocytes are _____ (cuboidal/squamous).
What is the advantage of having thin squamous cells that line the alveoli?
Maximum gas exchange is permitted by thin cells
Describe clara cells and their three functions.
Nonciliated columnar pneumocytes with granules that secrete a component of surfactant and degrade toxins and act as reserve cells
Which cells are responsible for clearing debris that accumulates in the alveoli?
In pulmonary gas exchange, _____ (carbon dioxide/oxygen) diffuses from the capillary lumen to the alveolar space, while _____ (carbon dioxide/oxygen) diffuses from the alveolar space to the capillary lumen.
Carbon dioxide; oxygen
Surfactant is secreted from the lamellar bodies of ____ (type I/type II/clara cell) pneumocytes.
An oxygen molecule is in the alveolus. In order, what cells will it cross to be able to bind to heme in the red blood cells?
To pass through the alveolar space to the capillary lumen, oxygen diffuses across the type I pneumocyte and then the endothelial cell
A carbon dioxide molecule is in the red blood cell within the capillary lumen. In order, what cells will it cross before it is exhaled?
The majority of carbon dioxide will exit red blood cells as bicarbonate (in exchange for chloride), cross the endothelial cell, then the type I pneumocyte to enter the alveolar space
Along with pneumocytes, which phagocytic cells can be found in the alveolar space?
Each bronchopulmonary segment has what three structures in the center?
A tertiary bronchus and two arteries (remember: Arteries run with Airways)
What two arteries are found in the center of each bronchopulmonary segment?
A bronchial artery and a pulmonary artery
What two structures are found along the borders of each bronchopulmonary segment?
Veins and lymphatics
Pulmonary _____ (arteries/veins) carry _____ (deoxygenated/oxygenated) blood from the right side of the heart to the lungs.
How does pulmonary arterial pressure fluctuate depending on the stage of the cardiac cycle?
It does not fluctuate; elastic walls maintain relatively constant pulmonary arterial pressure during the cardiac cycle
How many lobes does the right lung have? How many does the left lung have?