Blood cell collapse when placed in water containing less than 0.9% (\(\frac{mass}{volume}\)) NaCl solution. This is due to:

gain of water by osmosis

Blood cell collapse, when placed in water containing less than 0.9% (\(\frac{mass}{volume}\)) NaCl solution. This is due to gain of water by osmosis.

When the concentration is less than 0.9% NaCl solution, water will flow into the cells, and they would swell.