What changes will you observe when RBCs are placed in hypertonic, hypotonic, and isotonic solutions?
Understanding Red Blood Cell (RBC) Reactions to Different Solutions
Options:
- (a) RBCs swell in hypertonic, shrink in hypotonic, and maintain in isotonic.
- (b) RBCs shrink in hypertonic, swell in hypotonic, and maintain in isotonic.
- (c) RBCs maintain their size in all solutions.
- (d) RBCs burst in hypertonic, shrink in hypotonic, and maintain in isotonic.
Final answer:
Red blood cells (RBCs) shrink in a hypertonic solution as water moves out, swell in a hypotonic solution as water moves in, and maintain their normal volume and shape in an isotonic solution where there's no net movement of water.
Explanation:
When we expose red blood cells (RBCs) to different types of solutions, they react in particular ways that are determined by the tonicity of these solutions. So, when RBCs are placed in a hypertonic solution, where the concentration of solutes (salts, sugars, etc.) is higher outside the cells than inside, water moves out of the RBCs causing them to shrink or shrivel. This happens because water moves from areas of lower solute concentration (inside the RBC) to areas of higher solute concentration (the hypertonic solution).
In contrast, when RBCs are placed in a hypotonic solution, where the concentration of solutes is lower outside than inside the cells, the water moves into the RBCs causing them to swell as they try to equalize the solute concentration. This can cause RBCs to potentially burst if the water influx is too great.
Lastly, in an isotonic solution, the concentration of solutes inside and outside the cells is the same, meaning there is no net movement of water. Resultantly, the RBCs maintain their normal volume and shape. Thus, the correct option is (b) RBCs shrink in hypertonic, swell in hypotonic, and maintain in isotonic.