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...

Transmission electron micrograph showing the inactive X chromosome (labeled Sex Chromatin), and also known as the Barr body, adpressed to the nucleolus in this section through the nucleus of a spinal ...

Mouse 3T3 fibroblast immunostained for the nucleolar protein nucleostemin (left, green) and UBF (right, red) marking nucleolar fibrillar centers.

Thin section showing nucleolus of a Human neuroblastoma SK-N-SH cell imaged with a FEI Tecnai 20 energy filtered electron microscope at 200 KV and a 20 eV energy window. Overlay of net phosphorus dist...

Thin section showing nucleolus of a Human neuroblastoma SK-N-SH cell imaged with a FEI Tecnai 20 energy filtered electron microscope at 200 KV and a 20 eV energy window. Overlay of net phosphorus dist...

Transmission electron micrograph of the salivary gland of the tick Rhipicelphals appendiculatus illustrating the dramatic difference in nuclear size seen in different cell types. Here, the large (prob...

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...

Thin section showing nucleolus of a Human neuroblastoma SK-N-SH cell imaged with a FEI Tecnai 20 energy filtered electron microscope at 200 KV and a 20 eV enegy window. Left panel shows 'phosphorus' i...

Thin section showing nucleolus of a Human neuroblastoma SK-N-SH cell imaged with a FEI Tecnai 20 energy filtered electron microscope at 200 KV and a 20 eV energy window. Overlay of net phosphorus dist...

Mouse 3T3 fibroblast stained for the nucleolar protein nucleostemin (left, green) and signal recognition particle RNA SRP-RNA (right, red).