Human red blood cells contain 0.9% sodium chloride as a component of their cytoplasm. What would happen if an IV solution containing 1.5% sodium chloride is introduced into a person?

Question

a
The red blood cells would first absorb water across their cell membrane, then lose water across their cell membrane.
b
Their red blood cells would absorb water across their cell membrane and begin to swell.
c
The red blood cells will first lose water across their cell membrane, then absorb water across their cell membrane.
d
Their red blood cells would lose water across their cell membrane and begin to shrink.

Answer 1

The correct answer is:

d. Their red blood cells would lose water across their cell membrane and begin to shrink.

Here's the reasoning: Human red blood cells are in an isotonic environment when surrounded by a 0.9% sodium chloride solution. If a hypertonic solution (1.5% sodium chloride) is introduced into the body, the concentration of solutes outside the red blood cells would be higher than inside. Consequently, water would move out of the red blood cells in an attempt to equalize the solute concentrations, leading to cell shrinkage (crenation).