NUR 4909 MEMBRANE TRANSPORT EXAM WITH CORRECT
ANSWERS 2026/2027 || ADVANCED NURSING PHYSIOLOGY REVIEW
|| CELL MEMBRANE FUNCTION & TRANSPORT MECHANISMS ||
VERIFIED QUESTIONS & ACCURATE ANSWERS || HIGH-YIELD
STUDY GUIDE || COMPLETE TEST BANK || GRADED A+
Lipid bilayers are differentially permeable to different types of molecules.
Which types of molecules can readily cross such bilayers without the help of
transport proteins? Name some of the physical properties of molecules that
prevent them from freely diffusing across lipid bilayers. - CORRECT
ANSWER -Small uncharged lipid soluble molecules cross bilayers easily
without help.
Large molecules, charged molecules, and hydrophilic molecules do not diffuse
readily across the membrane.
What factors influence the rate of diffusion across a membrane? - CORRECT
ANSWER --concentration gradient
-permeability of molecule
-membrane surface area
-membrane thickness
-temp(should not vary within the body)
-molecular size
Give examples of how membranes might be altered in a biological system to
change the rate of diffusion. - CORRECT ANSWER -Membranes could be
altered by increasing the thickness of the diffusion barrier (ex: edema),
alteration of membrane surface area (ex: emphysema), and in the case of water,
insertion of more channels although this would not be diffusion as strictly
defined.
Can you give a few examples of where diffusion is important for proper
physiological function? - CORRECT ANSWER -Diffusion is important for
gas exchange, transport of small molecules and membrane permeable drugs into
cells (alcohol, nicotine, steroids, anesthetics, etc.).
, Define diffusion, osmosis, active transport, and passive transport. - CORRECT
ANSWER --Diffusion:
-Osmosis:
-Active transport: requires ATP energy, moves against concentration gradient
-Passive transport: does not require ATP, moves down concentration gradient
How are large molecules transported across cell membranes? - CORRECT
ANSWER -Transport proteins or vesicular transport (if very large)
The opening of membrane channels can be controlled by "gates". What factors
can cause these gates to open? - CORRECT ANSWER --Mechanical
stimulation
-Ligand binding
-Change in membrane voltage
Name 3 functions of the sodium potassium pump. - CORRECT ANSWER --
Maintain ionic gradients (important to resting potential)
-Provides gradients for secondary active transporters
-Maintains cell volume by keeping ionic concentrations constant.
How do passive transport and active transport differ? - CORRECT ANSWER
--Active transport requires ATP, passive does not
-Active moves a substance against its concentration gradient, while passive
moves a substance down its concentration gradient
Is facilitated diffusion active or passive? - CORRECT ANSWER -Passive
If the vessels of the brain have a reduced amount of plasma proteins, what effect
would you expect this to have on the volume of extracellular fluid surrounding
ANSWERS 2026/2027 || ADVANCED NURSING PHYSIOLOGY REVIEW
|| CELL MEMBRANE FUNCTION & TRANSPORT MECHANISMS ||
VERIFIED QUESTIONS & ACCURATE ANSWERS || HIGH-YIELD
STUDY GUIDE || COMPLETE TEST BANK || GRADED A+
Lipid bilayers are differentially permeable to different types of molecules.
Which types of molecules can readily cross such bilayers without the help of
transport proteins? Name some of the physical properties of molecules that
prevent them from freely diffusing across lipid bilayers. - CORRECT
ANSWER -Small uncharged lipid soluble molecules cross bilayers easily
without help.
Large molecules, charged molecules, and hydrophilic molecules do not diffuse
readily across the membrane.
What factors influence the rate of diffusion across a membrane? - CORRECT
ANSWER --concentration gradient
-permeability of molecule
-membrane surface area
-membrane thickness
-temp(should not vary within the body)
-molecular size
Give examples of how membranes might be altered in a biological system to
change the rate of diffusion. - CORRECT ANSWER -Membranes could be
altered by increasing the thickness of the diffusion barrier (ex: edema),
alteration of membrane surface area (ex: emphysema), and in the case of water,
insertion of more channels although this would not be diffusion as strictly
defined.
Can you give a few examples of where diffusion is important for proper
physiological function? - CORRECT ANSWER -Diffusion is important for
gas exchange, transport of small molecules and membrane permeable drugs into
cells (alcohol, nicotine, steroids, anesthetics, etc.).
, Define diffusion, osmosis, active transport, and passive transport. - CORRECT
ANSWER --Diffusion:
-Osmosis:
-Active transport: requires ATP energy, moves against concentration gradient
-Passive transport: does not require ATP, moves down concentration gradient
How are large molecules transported across cell membranes? - CORRECT
ANSWER -Transport proteins or vesicular transport (if very large)
The opening of membrane channels can be controlled by "gates". What factors
can cause these gates to open? - CORRECT ANSWER --Mechanical
stimulation
-Ligand binding
-Change in membrane voltage
Name 3 functions of the sodium potassium pump. - CORRECT ANSWER --
Maintain ionic gradients (important to resting potential)
-Provides gradients for secondary active transporters
-Maintains cell volume by keeping ionic concentrations constant.
How do passive transport and active transport differ? - CORRECT ANSWER
--Active transport requires ATP, passive does not
-Active moves a substance against its concentration gradient, while passive
moves a substance down its concentration gradient
Is facilitated diffusion active or passive? - CORRECT ANSWER -Passive
If the vessels of the brain have a reduced amount of plasma proteins, what effect
would you expect this to have on the volume of extracellular fluid surrounding
