developing endosperm of wheat--a stereological analysis

A stereological analysis of light and electron micrographs of wheat endosperm during grain formation and development provides information on a range of parameters of cell structure. The cell volume increases approximately ten-fold; mitochondrial number per cell increases but the individual mitochondrial volume decreases, the overall volume fraction of the cell occupied by mitochondria remaining fairly constant. Amyloplast division stops before cell division, resulting in the distribution of previously-formed plastids; there are differences in starch granule growth rate in different cell layers of the endosperm. The rough endoplasmic reticulum increases four-fold in area per cell and its surface-to-volume ratio increases just prior to protein deposition.