1. A turning inward, upside down, or in any direction contrary to the existing one.
2. Conversion of a disaccharide or polysaccharide by hydrolysis into a monosaccharide; specifically, the hydrolysis of sucrose to d-glucose and d-fructose; so called because of the change in optic rotation.
3. Alteration of a DNA molecule made by removing a fragment, reversing its orientation, and putting it back into place.
4. Heat-induced transition of silica, in which the quartz tridymite or cristobalite changes its physical properties as to thermal expansion.
5. Conversion of a chiral center into its mirror image.
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