Ghosts of erythrocytes are the direct result of the process called hemolysis or rupture of these cells. The shape of the red blood cells is determined by osmotic forces, that is, by the amount of water inside them. In a hypertonic solution (with more osmolarity than the blood plasma) the erythrocytes are reduced in size by the osmotic loss of water and adopt a characteristic star shape. In a hypotonic solution, on the other hand, the erythrocytes increase in size due to the uptake of water and assume the spherical shape. The stretching of the erythrocyte membrane makes it permeable, so the hemoglobin is filtered out of the cell. In this way are the almost colorless structures called "ghosts" or ghosts.
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