ACTUAL EXAM 250 QUESTIONS AND CORRECT
DETAILED ANSWERS WITH
RATIONALES|ALREADY GRADED A+||GALEN
COLLEGE OF NURSIN 2025/2026
What is ventilation? - Answer-the movement of air into and out of the lungs
What is perfusion? - Answer-the circulation of blood through the lungs
What are central chemoreceptors responsive to? - Answer-increased H+ in the
brain ECF;
increased PaCO2;
"hypercarbic drive"
What are peripheral chemoreceptors responsive to? - Answer-decreased pH;
increased PaCO2;
decreased PaO2;
"hypoxic drive"
What are elastic forces? - Answer-lungs recoil due to elastin, collagen, fibrin
,What are surface forces? - Answer-surface tension due to water-air interface
What is airway resistance? - Answer-opposition to flow caused by the forces of
friction; primarily determined by airway radius
What is the distensibility of the lungs? - Answer-ease with which the lungs can be
inflated
What factors affect lung perfusion? - Answer-lung capacitance;
low resistance system;
flow influenced by gravity;
resistance primarily determined by vessel radius
What does hypoxia lead to? - Answer-vasoconstriction of pulmonary vessels
What does prolonged hypoxia lead to? - Answer-pulmonary hypertension
What factors affect alveolar-capillary diffusion? - Answer-capillary permeability;
surface area available for diffusion;
concentration gradient for the gas;
distance for diffusion
,What causes right shifts (decreased affinity) in Hemoglobin-O2 affinity? - Answer-
acidemia;
hyperthermia;
hypercarbia
What causes left shifts (increased affinity) in Hemoglobin-O2 affinity? - Answer-
alkalemia;
hypothermia;
hypocarbia
What is lung distensibility increased in? - Answer-neonates and children;
emphysema
What is lung distensibility decreased in? - Answer-elderly;
pneumonia, pulmonary edema, ARDS, atelectasis, fibrosis
What is surfactant? - Answer-complex substance lining the alveoli and smallest
bronchioles containing phospholipids and a number of apoproteins which reduces
surface tension throughout the lungs, thereby contributing to its general
compliance;
stabilizes the alveoli and keeps them dry
, What produces surfactant? - Answer-produced by the Type II alveolar cells
What is Ohm's law? - Answer-velocity = driving force/resistance
What is Poiseuille law? - Answer-resistance = (8 x viscosity x length) / (pi x
radius^4)
What happens if the radius in the lungs goes down? - Answer-the resistance goes
up
How is the ventilation distributed in the lungs? - Answer-the top of the lungs are
more distended and less compliant whereas the lower lung is small and highly
compliant
What is hypoxemia? - Answer-deficient blood oxygen;
low PaO2;
low O2 saturation
What is hypoxia? - Answer-decreased tissue oxygen
What is hypoxic hypoxia? - Answer-decreased tissue oxygen caused by decreased
respirations