GMS 6401 PRACTICE EXAM
QUESTIONS AND DETAILED
SOLUTIONS 2026
▶ rhabdomyolysis. Answer: muscle crush leads to cardiac cell electrical
imbalance
crush releases K+ into plasma
hyperkalemia
excess K+ goes thru leaky channel into cardiac cells
cardiac cell potential less negative (depolarized)
leads to cardiac arrhythmias
▶ what percent of the total body weight is water. Answer: 60%
▶ what % of the body weight is extracellular fluid. Answer: 20%
▶ what % if the body weight is intracellular fluid. Answer: 40%
▶ what percent of the body weight is interstitial fluid. Answer: 3/4 of ECF
▶ what % of the body weight is plasma. Answer: 4-5%
1/4 of ECF
▶ what are the components of the blood. Answer: hematocrit is 45%
plasma is 55%
▶ what % of the body weight is blood volume. Answer: 8%
▶ what are the main body fluid compartments. Answer: intracellular
extracellular
▶ what are the components of the extracellular fluid. Answer: interstitial
(between cells)
plasma (in blood)
, ▶ what is the plasma membrane. Answer: between intra and extracellular
compartments
complex lipid bilayer
has transporters, carriers, pores
▶ what molecule is able to move freely between all compartments
(intracellular, interstitial, and plasma). Answer: water
▶ what is the dilution principle. Answer: an exact quantity of a soluble
substance is dissolved in an unknown volume of water, after equilibration,
when the soluble substance is evenly diluted throughout the water, the
concentration can be ,measured
volume can be found by dividing the exact quantity of the soluble
substance added by the concentration at equilibrium (look at slide for
formulas)
▶ what are the criteria for measurement of volume of a particular fluid
compartment. Answer: substance must be freely distributed through entire
compartment
must be non toxic
not metabolized
easily measured
▶ example of measuring an unknown volume. Answer: add 100 g of blue
dye
mix until concentration equilibrates
concentration at equilibrium is 20 g/liter
what is volume?
(100g)/(20 g/L) --> 5 liters
▶ how do we measure plasma volume. Answer: use 131 iodine-labelled
albumin or EVANS BLUE dye
this binds to plasma proteins and stays in plasma
▶ how do we measure the extracellular fluid volume (plasma and interstitial
fluid). Answer: cannot enter cell, must stay in plasma & interstitial fluid
use inulin (sugar that is foreign to body)
also can use radio labeled sodium or chloride
QUESTIONS AND DETAILED
SOLUTIONS 2026
▶ rhabdomyolysis. Answer: muscle crush leads to cardiac cell electrical
imbalance
crush releases K+ into plasma
hyperkalemia
excess K+ goes thru leaky channel into cardiac cells
cardiac cell potential less negative (depolarized)
leads to cardiac arrhythmias
▶ what percent of the total body weight is water. Answer: 60%
▶ what % of the body weight is extracellular fluid. Answer: 20%
▶ what % if the body weight is intracellular fluid. Answer: 40%
▶ what percent of the body weight is interstitial fluid. Answer: 3/4 of ECF
▶ what % of the body weight is plasma. Answer: 4-5%
1/4 of ECF
▶ what are the components of the blood. Answer: hematocrit is 45%
plasma is 55%
▶ what % of the body weight is blood volume. Answer: 8%
▶ what are the main body fluid compartments. Answer: intracellular
extracellular
▶ what are the components of the extracellular fluid. Answer: interstitial
(between cells)
plasma (in blood)
, ▶ what is the plasma membrane. Answer: between intra and extracellular
compartments
complex lipid bilayer
has transporters, carriers, pores
▶ what molecule is able to move freely between all compartments
(intracellular, interstitial, and plasma). Answer: water
▶ what is the dilution principle. Answer: an exact quantity of a soluble
substance is dissolved in an unknown volume of water, after equilibration,
when the soluble substance is evenly diluted throughout the water, the
concentration can be ,measured
volume can be found by dividing the exact quantity of the soluble
substance added by the concentration at equilibrium (look at slide for
formulas)
▶ what are the criteria for measurement of volume of a particular fluid
compartment. Answer: substance must be freely distributed through entire
compartment
must be non toxic
not metabolized
easily measured
▶ example of measuring an unknown volume. Answer: add 100 g of blue
dye
mix until concentration equilibrates
concentration at equilibrium is 20 g/liter
what is volume?
(100g)/(20 g/L) --> 5 liters
▶ how do we measure plasma volume. Answer: use 131 iodine-labelled
albumin or EVANS BLUE dye
this binds to plasma proteins and stays in plasma
▶ how do we measure the extracellular fluid volume (plasma and interstitial
fluid). Answer: cannot enter cell, must stay in plasma & interstitial fluid
use inulin (sugar that is foreign to body)
also can use radio labeled sodium or chloride
