How is DNA made into protein?

DNA is first transcribed into a messenger RNA molecule called mRNA, RNA is similar to DNA but contains Uracil instead of Thymine. RNA polymerase recruits nucleotides to build the mRNA molecule and binds them together to create a transcript. Complimentary base pairing is used to faithfully transcribe the message from the DNA sequence into an mRNA molecule. In RNA cytosine pairs with guanine and in RNA adenine pairs with uracil instead of thymine. A DNA sequence reading TACAATCGCTAG would be transcribed into a mRNA molecule reading AUGUUAGCGAUC The DNA template molecule is copied by RNA polymerase in the nucleus to make a message that moves into the cytoplasm to be translated into protein. The mRNA molecule binds to a ribosome which reads the DNA molecule in triplet "codons". tRNA molecules transfer amino acids to the ribosome and the "anticodon" (a specific region of the tRNA molecule)  is complementary to the triplet codon in the active site of the ribosome. The first amino acid in all proteins is methionine (encoded by the codon AUG) so a tRNA with the anticodon TAC will transport a methionine amino acid into the ribosome where it will be attached to the subsequent amino acids as the next codons are read. Eventually a stop codon will be read by the ribosome, at this stage the newly synthesised amino acid string will be released from the ribosome and will be folded into a secondary and tertiary structure as appropriate.  The first process (making mRNA from DNA) is known as transcription and the second (making mRNA into protein) is translation. 

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