ribosome(redirected from P (peptidyl) site)
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Related to P (peptidyl) site: Peptidyl transferase, E site
A structure composed of RNA and protein, present in large numbers in the cytoplasm of living cells and serving as the site for assembly of polypeptides encoded by messenger RNA.
ri′bo·so′mal (-sō′məl) adj.
(Biochemistry) any of numerous minute particles in the cytoplasm of cells, either free or attached to the endoplasmic reticulum, that contain RNA and protein and are the site of protein synthesis
[C20: from ribo(nucleic acid) + -some3]
a tiny, mitten-shaped organelle occurring in great numbers in the cell cytoplasm and functioning as the site of protein manufacture.
A sphere-shaped structure within the cytoplasm of a cell that is composed of RNA and protein and is the site of protein synthesis. Ribosomes are often attached to the membrane of the endoplasmic reticulum. See more at cell.
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|Noun||1.||ribosome - an organelle in the cytoplasm of a living cell; they attach to mRNA and move down it one codon at a time and then stop until tRNA brings the required amino acid; when it reaches a stop codon it falls apart and releases the completed protein molecule for use by the cell; "the ribosome is the site of protein synthesis"|