ribosome

American  

[rahy-buh-sohm] / ˈraɪ bəˌsoʊm /

noun

Cell Biology.

1. a tiny, somewhat mitten-shaped organelle occurring in great numbers in the cell cytoplasm either freely, in small clusters, or attached to the outer surfaces of endoplasmic reticula, and functioning as the site of protein manufacture.

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ribosome British  

/ ˈraɪbəˌsəʊm /

noun

1. 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

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ribosome Scientific  

/ rī′bə-sōm′ /

1. 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 free in the cytoplasm and often attached to the membrane of the endoplasmic reticulum. Ribosomes exist in both eukaryotic and prokaryotic cells. Plastids and mitochondria in eukaryotic cells have smaller ribosomes similar to those of prokaryotes.

2. See more at cell

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ribosome Cultural  

1. A small, ball-like structure in the cell, made of proteins and RNA molecules, that serves as a platform on which the cell's proteins are made.

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Other Word Forms

• ribosomal adjective

Etymology

Origin of ribosome

First recorded in 1955–60; ribo(se) + -some ³

Example Sentences

By combining biochemical experiments with cryo-electron microscopy, the research group demonstrated that ribosome collisions serve as the main activation cue for ZAK.

From Science Daily • Nov. 25, 2025

Ribosomal RNA is often modified with chemical tags that can alter the shape and function of the ribosome.

From Science Daily • Nov. 29, 2024

"We know there is an interaction between the RNAP, the ribosome, transcription factors, proteins and mRNA," said U-M senior scientist Adrien Chauvier, one of four co-leaders of the study.

From Science Daily • Nov. 28, 2024

The team developed a mechanistic framework to show how the various components of the complex work together to bring freshly transcribed mRNAs to the ribosome and act as bridges between transcription and translation.

From Science Daily • Nov. 28, 2024

The addition of the ion was critical: with the solution supplemented with magnesium, the ribosome remained glued together, and Brenner and Jacob finally purified a minuscule amount of the messenger molecule out of bacterial cells.

From "The Gene" by Siddhartha Mukherjee