A red blood cell will undergo hemolysis in which of the following solutions?

• A. an isotonic solution
• B. a solution with equal solute concentration as the cytoplasm
• C. a hypotonic solution
• D. a hypertonic solution

Answer: (C)

Verified step by step guidance

1. Understand the concept of osmosis: Osmosis is the movement of water across a semipermeable membrane from a region of lower solute concentration to a region of higher solute concentration.
2. Define the terms isotonic, hypotonic, and hypertonic: An isotonic solution has the same solute concentration as the cytoplasm of the cell, a hypotonic solution has a lower solute concentration than the cytoplasm, and a hypertonic solution has a higher solute concentration than the cytoplasm.
3. Relate the effect of each solution type on a red blood cell: In an isotonic solution, there is no net movement of water, so the cell remains unchanged. In a hypotonic solution, water moves into the cell, causing it to swell and potentially burst (hemolysis). In a hypertonic solution, water moves out of the cell, causing it to shrink.
4. Focus on the hypotonic solution: Since a hypotonic solution has a lower solute concentration than the cytoplasm, water will move into the red blood cell, increasing internal pressure and leading to hemolysis.
5. Conclude the reasoning: Hemolysis occurs specifically in a hypotonic solution because the influx of water causes the cell membrane to rupture due to excessive swelling.