Freeze-drying process of biological specimens observed with a scanning electron microscope

A pit membrane was observed with a cryo-SEM during the course of dehydration at low temperatures. The freeze-drying process of sea-urchin eggs and parenchyma cells of higher plants was also examined with this microscope. Conditions for observation of frozen specimens in the native state were discussed on the basis of morphological studies of alterations such as shrinkage or deformation which appeared during the freeze-drying process.