Transmission electron micrograph of exocytosis taken from the rat pancreas. Images such as these indicated that secretory granules closely and selectively approach the apical membrane of the pancreat...

Stacks of rough endoplasmic reticulum (ER) cisternae seen in a transmission electron micrograph of a section through a secretory acinar cell from the bat exocrine pancreas. The rough ER is here involv...

Transmission electron micrograph of nucleus showing the characteristic features of glutaraldehyde fixation introduced as a primary fixative in 1962 and since used routinely. Chromatin appears differen...