Messenger RNA or mRNA has been named so because it carries the coded information from DNA for the synthesis of proteins. It carries the coded information in a number of base triplets called codons. It is transcribed on DNA by the enzyme RNA polymerase. Hence, its base sequence is complementary to DNA on which it has been synthesised. In eukaryotes, each gene transcribes its own mRNA, therefore the number of mRNAs corresponds to the number of genes. rRNA is a type of RNA that forms structural and functional components of ribosomes. tRNA is a class of RNA having structures with triplet nucleotide sequences that are complementary to the triplet nucleotide coding sequences of mRNA. It binds with amino acids and transfers them to ribosomes.