n.
1.short-chain RNA molecules present in the cell (in at least 20 varieties, each variety capable of combining with a specific amino acid) that attach the correct amino acid to the protein chain that is being synthesized at the ribosome of the cell (according to directions coded in the mRNA)
Idiom of the Day
take up (space or room)
to fill a space or room, to occupy space or room
The old chairs are taking up space in the garage.