What are the effects of surfactant secretion in the lungs?
Decreased alveolar surface tension, increased compliance, and decreased work of inspiration
Name five important molecules produced by the lungs.
Surfactant, prostaglandins, histamine, angiotensin-converting enzyme, and kallikrein
In addition to inactivating bradykinin, what other reaction does angiotensin-converting enzyme catalyze?
The conversion of angiotensin I to angiotensin II
Angiotensin-converting enzyme inhibitors increase bradykinin, which leads to which two common adverse effects?
Cough and angioedema
A deficiency of surfactant leads to what neonatal condition?
Respiratory distress syndrome
Give the equation for calculating collapsing pressure.
Collapsing pressure = 2 × tension / radius
What is the effect of histamine on the airways in the lung?
In the lung, _____ (angiotensin-converting enzyme/kallikrein) inactivates bradykinin, _____ (angiotensin-converting enzyme/kallikrein) activates bradykinin.
Angiotensive converting enzyme; kallikrein
What is the term for the volume of air in the lungs after maximal expiration?
What is the term for the volume of air that can still be breathed out after normal expiration?
Expiratory reserve volume
What is the term for the volume of air that moves into the lungs with each quiet inspiration?
How much is the typical tidal volume?
What is the term for the volume of air in excess of tidal volume that moves into the lung on maximum inspiration?
Inspiratory reserve volume
What is the term for the maximum volume of air that can be inhaled and exhaled?
Vital capacity equals the sum of what three lung volumes?
Tidal volume, inspiratory reserve volume, and expiratory reserve volume
The residual volume plus the expiratory reserve volume equals what?
The functional reserve capacity
Describe the functional reserve capacity.
The volume left in the lungs after normal expiration
The inspiratory reserve volume plus the tidal volume equals what?
The inspiratory reserve volume plus the tidal volume plus the expiratory reserve volume plus the residual volume equals what?
Total lung capacity
What is the term for the lung volume that includes all capacity except the residual volume?
Which lung volume cannot be measured on spirometry: inspiratory reserve volume, tidal volume, expiratory reserve volume, or residual volume?
What is the formula for calculating dead space volume given an arterial blood gas and a measurement of exhaled carbon dioxide?
Dead space volume = tidal volume × [(partial arterial pressure of carbon dioxide - partial expiratory pressure of carbon dioxide) / partial arterial pressure of carbon dioxide]
Physiological dead space includes the anatomical dead space of the _____ (conducting/respiratory) airways plus the functional dead space in _____ (alveoli/bronchioles).
Which section of the healthy lung contributes more to functional dead space: the apex or the base?
Describe the natural tendency of movement of the lung and chest wall.
The lungs tend to collapse inward and chest wall springs outward
At the point of functional residual capacity (i.e., at the end of a normal expiration), what is the value of the air pressure within the lungs?
At functional residual capacity, the pressure within the lungs is equal to atmospheric pressure
What balances the inward elastic pull of the lung at the point of functional residual capacity (i.e. at the end of a normal expiration)?
The outward pull of the chest wall
How many polypeptide subunits make up hemoglobin?
Adult hemoglobin is formed from two _____ subunits and two _____ subunits.
What are the two conformational forms of hemoglobin?
Relaxed and taut