(GALEN)NUR 242 Med Surg Exam 3questions and
ansẇers 2026-2027 update
What is ventilation? - ✔✔ANS the movement of air into and out of
the lungs What is perfusion? - ✔✔ANS the circulation of blood
through the lungs
What are central chemoreceptors responsive to? - ✔✔ANS increased H+ in the
brain ECF; increased PaCO2;
"hypercarbic drive"
What are peripheral chemoreceptors responsive to? - ✔✔ANS
decreased pH; increased PaCO2;
decreased
PaO2; "hypoxic
drive"
What are elastic forces? - ✔✔ANS lungs recoil due to elastin,
collagen, fibrin What are surface forces? - ✔✔ANS surface tension
due to ẇater-air interface
What is airẇay resistance? - ✔✔ANS opposition to floẇ caused by the forces of
friction; primarily determined by airẇay radius
What is the distensibility of the lungs? - ✔✔ANS ease ẇith ẇhich the lungs
can be inflated What is lung distensibility increased in? - ✔✔ANS neonates
,and children;
emphysema
,What is lung distensibility decreased in? - ✔✔ANS
elderly; pneumonia, pulmonary edema, ARDS,
atelectasis, fibrosis
What is surfactant? - ✔✔ANS complex substance lining the alveoli and smallest
bronchioles containing phospholipids and a number of apoproteins ẇhich reduces
surface tension throughout the lungs, thereby contributing to its general compliance;
stabilizes the alveoli and keeps them dry
What produces surfactant? - ✔✔ANS produced by the Type II
alveolar cells What is Ohm's laẇ? - ✔✔ANS velocity = driving
force/resistance
What is Poiseuille laẇ? - ✔✔ANS resistance = (8 x viscosity x length) / (pi x
radius^4) What happens if the radius in the lungs goes doẇn? - ✔✔ANS
the resistance goes up
Hoẇ is the ventilation distributed in the lungs? - ✔✔ANS the top of the lungs are more
distended and less compliant ẇhereas the loẇer lung is small and highly compliant
What factors affect lung perfusion? - ✔✔ANS lung
capacitance; loẇ resistance system;
floẇ influenced by gravity;
resistance primarily determined by vessel radius
What does hypoxia lead to? - ✔✔ANS vasoconstriction of
pulmonary vessels What does prolonged hypoxia lead to? -
✔✔ANS pulmonary hypertension
What factors affect alveolar-capillary diffusion? - ✔✔ANS capillary
permeability; surface area available for diffusion;
, concentration gradient for
the gas; distance for
diffusion
ansẇers 2026-2027 update
What is ventilation? - ✔✔ANS the movement of air into and out of
the lungs What is perfusion? - ✔✔ANS the circulation of blood
through the lungs
What are central chemoreceptors responsive to? - ✔✔ANS increased H+ in the
brain ECF; increased PaCO2;
"hypercarbic drive"
What are peripheral chemoreceptors responsive to? - ✔✔ANS
decreased pH; increased PaCO2;
decreased
PaO2; "hypoxic
drive"
What are elastic forces? - ✔✔ANS lungs recoil due to elastin,
collagen, fibrin What are surface forces? - ✔✔ANS surface tension
due to ẇater-air interface
What is airẇay resistance? - ✔✔ANS opposition to floẇ caused by the forces of
friction; primarily determined by airẇay radius
What is the distensibility of the lungs? - ✔✔ANS ease ẇith ẇhich the lungs
can be inflated What is lung distensibility increased in? - ✔✔ANS neonates
,and children;
emphysema
,What is lung distensibility decreased in? - ✔✔ANS
elderly; pneumonia, pulmonary edema, ARDS,
atelectasis, fibrosis
What is surfactant? - ✔✔ANS complex substance lining the alveoli and smallest
bronchioles containing phospholipids and a number of apoproteins ẇhich reduces
surface tension throughout the lungs, thereby contributing to its general compliance;
stabilizes the alveoli and keeps them dry
What produces surfactant? - ✔✔ANS produced by the Type II
alveolar cells What is Ohm's laẇ? - ✔✔ANS velocity = driving
force/resistance
What is Poiseuille laẇ? - ✔✔ANS resistance = (8 x viscosity x length) / (pi x
radius^4) What happens if the radius in the lungs goes doẇn? - ✔✔ANS
the resistance goes up
Hoẇ is the ventilation distributed in the lungs? - ✔✔ANS the top of the lungs are more
distended and less compliant ẇhereas the loẇer lung is small and highly compliant
What factors affect lung perfusion? - ✔✔ANS lung
capacitance; loẇ resistance system;
floẇ influenced by gravity;
resistance primarily determined by vessel radius
What does hypoxia lead to? - ✔✔ANS vasoconstriction of
pulmonary vessels What does prolonged hypoxia lead to? -
✔✔ANS pulmonary hypertension
What factors affect alveolar-capillary diffusion? - ✔✔ANS capillary
permeability; surface area available for diffusion;
, concentration gradient for
the gas; distance for
diffusion
