Transmission electron micrograph of Leydig cell nucleus from the domestic boar contains a region (arrow) thought to represent the single X chromosome which is largely heterochromatic. The chromosome i...

High resolution of a daughter micronucleus in anaphase of a dividing cell of Didinium nasutum. The chromosomes are compacted into one large heterochromatic body. Remnants of the mitotic division spind...

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

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...

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...

Daughter micronucleus in anaphase of a dividing cell of Didinium nasutum. The chromosomes are compacted into one large heterochromatic body. Remnants of the mitotic division spindle remain inside the ...

High resolution transmission electron micrograph of a portion of the macronucleus of Opercularia coarctata containing irregularly shaped heterochromatin bodies and elliptical nucleoli. Ribosome-like p...

Transmission electron micrograph of a pancreatic acinar cell from the bat Myotis lucifugus showing the 'classic' ultrastructural features of the nucleus after glutaraldehyde fixation. The large darkly...