1|Page
NBME PHYSIOLOGY 2025| BRAND NEW ACTUAL
EXAM WITH 100% VERIFIED QUESTIONS AND
CORRECT SOLUTIONS| GUARANTEED VALUE PACK|
ACE YOUR GRADES.
Gap Junctions - (answer)attachment between cells that permit intercellular
communication (i.e. current flow and electrical coupling between myocytes)
J= -PA (C1-C2)
J= (1x10^-5)(100)[(20/100)-(10/100)]
J= 1x10-4 mg/sec - (answer)The urea conc. of blood is 10 mg/ 100mL the urea
conc of proximal tubular fluid is 20 mg/ 100 mL. if the permeability to urea is
1x10^-5 cm/sec and the surface area is 100 cm^2 what is the magnitude and
direction of the urea flux (diffusion)?
2 K+ for 3 Na+
Digitalis
(cardiac glycoside drug) - (answer)Na/K ATPase exchanges ___ K for ___ Na.
Specific inhibitor of the Na/K ATPase?
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SERCA - (answer)Ca++ ATPase in the sarcoplasmic and endoplasmic reticulum?
Omeprazole (proton pump inhibitor) - (answer)The H/K ATPase that pumps
protons into the gastric lumen (against their conc. gradient) is inhibited by what
drug?
Osmosis - (answer)Flow of water across a semipermeable membrane from a
solution with low solute conc. to a solution with high solute conc. ?
Increases - (answer)Osmotic pressure ___________ when solute conc. increases.
1 M CaCl2 because the conc. of particles is higher. - (answer)Which has a higher
osmotic pressure: 1 M CaCl2 or 1 M KCl?
Isotonic
Hypertonic
Hypotonic
**Water flows from the hypotonic to the hypertonic solution. - (answer)If two
solutions have the same osmotic pressure, they are _________
,3|Page
If one solution has a higher osmotic pressure than the other, it is _____________
If one solution has a lower osmotic pressure than the other, it is __________
Reflection coefficient
Rf= 1 means the solute is IMPERMEABLE (100% reflection)
Rf= 0 means the solute is COMPLETELY PERMEABLE - (answer)A number between
zero and 1 that describes the ease with which a solute permeates a membrane?
Rf= 1
Rf=0 - (answer)reflection coefficient of serum albumin? (a large solute)
Reflection coefficient of urea? (a small solute)
Small Cations
*will exclude large molecules and anions - (answer)A small ion channel lined with
negatively charged groups will be selective for?
, 4|Page
Equilibrium potential
**At electrochemical equilibrium, the chemical and electrical driving forces that
act on an ion are *equal and opposite*, and no more net diffusion of the ion
occurs. - (answer)Refers to the potential difference that would exactly balance
(oppose) the tendency for diffusion down a concentration gradient?
E Na= +65 mV
E Ca= +120 mV
E K= -85 mV
E Cl= -85 mV - (answer)Approximate equilibrium potentials in nerve and muscle?
E Na= ?
E Ca= ?
E K= ?
E Cl= ?
NBME PHYSIOLOGY 2025| BRAND NEW ACTUAL
EXAM WITH 100% VERIFIED QUESTIONS AND
CORRECT SOLUTIONS| GUARANTEED VALUE PACK|
ACE YOUR GRADES.
Gap Junctions - (answer)attachment between cells that permit intercellular
communication (i.e. current flow and electrical coupling between myocytes)
J= -PA (C1-C2)
J= (1x10^-5)(100)[(20/100)-(10/100)]
J= 1x10-4 mg/sec - (answer)The urea conc. of blood is 10 mg/ 100mL the urea
conc of proximal tubular fluid is 20 mg/ 100 mL. if the permeability to urea is
1x10^-5 cm/sec and the surface area is 100 cm^2 what is the magnitude and
direction of the urea flux (diffusion)?
2 K+ for 3 Na+
Digitalis
(cardiac glycoside drug) - (answer)Na/K ATPase exchanges ___ K for ___ Na.
Specific inhibitor of the Na/K ATPase?
,2|Page
SERCA - (answer)Ca++ ATPase in the sarcoplasmic and endoplasmic reticulum?
Omeprazole (proton pump inhibitor) - (answer)The H/K ATPase that pumps
protons into the gastric lumen (against their conc. gradient) is inhibited by what
drug?
Osmosis - (answer)Flow of water across a semipermeable membrane from a
solution with low solute conc. to a solution with high solute conc. ?
Increases - (answer)Osmotic pressure ___________ when solute conc. increases.
1 M CaCl2 because the conc. of particles is higher. - (answer)Which has a higher
osmotic pressure: 1 M CaCl2 or 1 M KCl?
Isotonic
Hypertonic
Hypotonic
**Water flows from the hypotonic to the hypertonic solution. - (answer)If two
solutions have the same osmotic pressure, they are _________
,3|Page
If one solution has a higher osmotic pressure than the other, it is _____________
If one solution has a lower osmotic pressure than the other, it is __________
Reflection coefficient
Rf= 1 means the solute is IMPERMEABLE (100% reflection)
Rf= 0 means the solute is COMPLETELY PERMEABLE - (answer)A number between
zero and 1 that describes the ease with which a solute permeates a membrane?
Rf= 1
Rf=0 - (answer)reflection coefficient of serum albumin? (a large solute)
Reflection coefficient of urea? (a small solute)
Small Cations
*will exclude large molecules and anions - (answer)A small ion channel lined with
negatively charged groups will be selective for?
, 4|Page
Equilibrium potential
**At electrochemical equilibrium, the chemical and electrical driving forces that
act on an ion are *equal and opposite*, and no more net diffusion of the ion
occurs. - (answer)Refers to the potential difference that would exactly balance
(oppose) the tendency for diffusion down a concentration gradient?
E Na= +65 mV
E Ca= +120 mV
E K= -85 mV
E Cl= -85 mV - (answer)Approximate equilibrium potentials in nerve and muscle?
E Na= ?
E Ca= ?
E K= ?
E Cl= ?
