Transmission electron micrographs showing details of nuclear pores in thin sections of an erythroblast (above) and endothelial cell (below). Pores appear to be filled with dark staining material in th...

Transmission electron micrograph of surface of nuclear envelope of guinea pig spermatocyte prepared by the Freeze-fracture technique shows the unusual clustering of nuclear pores in these cells. From...

Transmission electron micrograph of rat liver cell showing a grazing section through the nuclear envelope and illustrating the high density of nuclear pores in cells from a 1 day old animal. The cytop...

Transmission electron micrograph illustrating the 'classic' appearance of the nucleus in osmium tetroxide fixed material. In this pancreatic acinar cell nucleus, the only prominent feature is the lar...

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 stacked annulate lamellae from the oocyte of the sea urchin Arbacia. Annulate lamellae consist of sheets of membrane containing closely packed structures resemblin...

High resolution overview of Opercularia coarctata with macronucleus, cytoplasm, and section of the oral area. Specialized rough endoplasmic reticulum with modification into decorated tubules that lie ...

High resolution view of the nuclear envelope of both the macronucleus, seen here, and the micronucleus consists of 2 membranes containing numerous perforations called pores. Proteins are imported thro...

The nuclear envelope of both the macronucleus, seen here, and the micronucleus consists of 2 membranes containing numerous perforations called pores. Proteins are imported through these pores and ribo...

A freeze-fractured view of the nuclear envelope. The fracture in the middle of the figure exposes the cytosolic facing membrane. This can be distinguished by a fractured cytoplasmic organelle at the t...