How are proteins built using the information provided by a molecule of rna?

The RNA helps in the determination of the sequence of amino acids in proteins and polypeptides by a two-step procedure, that is, the transcription of DNA, which generates mRNA in the nucleus, and the translation of the mRNA to tRNA occurring at the ribosome in the cytoplasm.  

The association of ribosomal RNA takes place with a set of proteins to produce ribosomes. These composite structures move physically along the molecule of mRNA and catalyze the arrangement of amino acids into protein chains. They also associate with tRNAs and different other accessory molecules that play an essential role in the synthesis of protein.  

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