[noo-klee-uh-luh s, nyoo-]
- a conspicuous, rounded body within the nucleus of a cell.
Origin of nucleolus
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2018
Examples from the Web for nucleolus
Possibly the nucleolus is the Supra- and Subconscious element.Feminism and Sex-Extinction
The element x is present, but the nucleolus has disappeared.
The nucleus of the egg-cell is distinguished as the germinal vesicle, and its nucleolus as the germinal spot.The Anatomy of the Human Peritoneum and Abdominal Cavity
George. S. Huntington
In these latter stages the nucleolus has entirely faded out and nothing suggesting an accessory chromosome is present.
Spermatogonium, showing chromatin element (x) associated with a nucleolus (n).
- a small rounded body within a resting nucleus that contains RNA and proteins and is involved in the production of ribosomesAlso called: nucleole
C19: from Latin, diminutive of nucleus
Word Origin and History for nucleolus
1845, from Latin nucleolus, literally "a little nut," diminutive of nucleus (see nucleus).
Online Etymology Dictionary, © 2010 Douglas Harper
- A small, typically round granular body composed of protein and RNA in the nucleus of a cell, usually associated with a specific chromosomal site and involved in ribosomal RNA synthesis and the formation of ribosomes.
- A small, typically spherical granular body located in the nucleus of a eukaryotic cell, composed largely of protein and RNA. When the cell is not undergoing division, loops of DNA from one or more chromosomes extend into the nucleolus and direct the synthesis of ribosomal RNA and the formation of ribosomes. The ribosomes are eventually transferred out of the nucleus via pores in the nuclear envelope into the cytoplasm.
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