text: in translation and transcription, what are the functions of mrna, trna and rrna? translation has different tasks for the rna molecules than transcription. okay, first of all, let's differentiate between dna replication, transcription and translation.  dna replication is the process whereby dna makes an exact replica of itself. in this process, double stranded dna is first unwound by the enzyme helicase, and each strand of the dna serves as a template for the building of its complementary strand (at this point, free nucleotides are attached together in order to build the complementary strand - dna polymerase is the enzyme that takes care of this). afterwards, the enzyme ligase binds the two original strands to their two newly built complementary strands to give us 2 identical double stranded dna.  transcription is the process whereby rna is produced. as was the case with dna replication, a double stranded dna molecule is unwound, but this time only 1 strand gets its complenetary strand built, and that complementary strand becomes an rna strand (remember that rna is a single stranded molecule). also important to note is the fact that for all a's on the single strand of dna, we get u (uracil) on the rna strand when the nucleotides are base pairing.   translation is the process whereby rna (or more specifically, mrna, trna and rrna) build a protein. all of the three different types of rna i mentioned are made inside the nucleus. they then leave the nucleus through the nuclear pores and go to the ribosome. rrna (ribosomal rna) attaches to a ribosome and makes it function (the exact manner in whcih this is carried out is unknown - some say rrna acts as an enzyme when it's attached to a ribosome).  mrna (messenger rna) is carrying out the actual code to build the protein (i.e., it has the nucleotide bases - and as you should know, each three consecutive bases, also called a codon, code for a particular amino acid). mrna attaches to the ribosome as well, and lastly, trna (transfer rna) reads off the code on mrna and goes into the cytoplasm to pick up the amino acid the mrna codes for, and brings them back to the ribosome, where amino acids are attached together in the sequence that will yield the protein that is to be built.  remember that proteins are simply polymers of amino acids, that means proteins are made up of amino acids attached together - and the order in which the amino acids are attached together is peculiar to a particular protein.