Page "Cell nucleus" Paragraph 4

The nucleus was the first organelle to be discovered.

What is most likely the oldest preserved drawing dates back to the early microscopist Antonie van Leeuwenhoek ( 1632 – 1723 ).

He observed a " Lumen ", the nucleus, in the red blood cells of salmon.

Unlike mammalian red blood cells, those of other vertebrates still possess nuclei.