Transmission electron micrographs showing the unusual nucleolar structures in Sertoli cells of ruminants, with varying numbers of vesicles and tubules; the upper panel illustrates such an organization...

Transmission electron micrograph of a bone marrow orthochromatic erythroblast from guinea pig showing terminal differentiation in erythrocyte formation. Accompanying the cessation of most transcriptio...

Transmission electron micrograph of a cross section through the nucleolus from a Chinese hamster spermatogonium revealing a complex distribution of regions of varying granular textures.

Transmission electron micrograph of a section of a human polymorphonuclear neutrophil from circulating blood. Neutrophil nuclei are often lobed, as seen in the electron micrograph and light micrograph...

Transmission electron micrographs of Opossum spermatogonia showing different regions within the nucleolus. One region is more lightly staining and fine textured, the other denser and more coarsely tex...

Transmission electron micrograph showing the highly compact nucleolus in the salamander hepatocyte. A finer textured central region is surrounded by a coarser region.

In the upper panel, transmission electron microscopy reveals a tangled mass of ~30nm diameter nuclear chromatin fibers when the contents of the nucleus from erythrocytes of the newt Notophthalmus viri...

Transmission electron micrograph of cell division in an insect spermatocyte captured in late anaphase - telophase with cytokinesis in progress. The homologous chromosomes appear as darkly stained disc...

Transmission electron micrograph of isolated HeLa cell metaphase chromosome decondensed by removal of histones with dextran sulfate and heparin, centrifuged onto a carbon film and stained with uranyl ...

Transmission electron micrograph illustrating the unusually prominent fibrous nuclear lamina (arrows) seen in many invertebrates such as this leech ganglion cell. From Fawcett (1966) Am J. Anat. 119:...