Hartmann’s solution is commonly used for fluid maintenance and is administered intravenously. It is isotonic to blood and contains Na+, Cl–, K+, lactate, and Ca2+. When replacing fluids, it is essential to use solutions that are isotonic to blood, as an IV containing distilled water would lead to rapid hemolysis because:
a) osmotic pressure pulls water through the membrane to the interior of the cell.
b) the electrochemical gradient favors the inside of the RBC.
c) non-polar molecules cross the cell membrane into the water down their concentration gradient.
d) solute molecules rapidly diffuse into the water exterior to the RBC.
Click for Explanation
a) osmotic pressure pulls water through the membrane to the interior of the cell. Correct.
b) the electrochemical gradient favors the inside of the RBC. Incorrect, Osmolarity, osmotic pressure, and water diffusion have nothing to do with the electrochemical gradient.
c) non-polar molecules cross the cell membrane into the water down their concentration gradient. Incorrect, water diffuses across the cell membrane to cause the cell to burst. If solutes crossed the membrane to create an isotonic environment, the cell would not burst.
d) solute molecules rapidly diffuse into the water exterior to the RBC. Incorrect, See explanation c).
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