Number of Particles Per Unit Volume

Abstract

The mathematical basis of morphometry — including counting of particles — in translucent slices does not depend on the magnification. Nevertheless a difference exists in accomplishment between the morphometry in light and electron microscopy. This difference depends on the relation between the size of structure and the thickness of slice (furtherdown abbreviated with T). In light microscopy this relation (e.g.cells nuclei etc.) lies in general in the same class of size and we can recognize a classification of size of a structure without difficulties. In electron micrographs T is very small, and structures to be measured (e.g.organelles of cells, such as mitochondria etc.) are several times larger than T. In this case it is impossible to distinguish such a classification of structures. This is easy to explain because a larger body is cut into many profiles of different sizes.

This work was supported by the Deutsche Forschungsgemeinschaft.