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An enzyme attaches to the DNA molecule at the gene of interest.
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The two strands of DNA separate at that location.
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Complementary RNA nucleotides bond to the nitrogenous bases on one of the separated DNA strands.
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The chain of RNA nucleotides forms a single-stranded molecule of RNA by using the DNA strand as a template.
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When a stop codon is reached, the RNA strand separates from the DNA molecule, leaves the nucleus and goes through the nuclear membrane into the cytoplasm.
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The two DNA strands rejoin.
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The mRNA attaches to a ribosome, which contains proteins and ribosomal RNA (rRNA).
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Another type of RNA, transfer RNA (tRNA), brings amino acids to the ribosome in the order specified by the codon sequence on the mRNA.
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The anticodon of the tRNA, with its attached amino acid, pairs to the codon of the mRNA, which is attached to a ribosome.
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When a second tRNA with its specific amino acid pairs to the next codon in sequence, the attached amino acid breaks from the first tRNA and is bonded to the amino acid of the second tRNA.
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The ribosome forms a peptide bond between the amino acids, and an amino acid chain begins to form.
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The empty tRNA moves off and picks up another matching amino acid from the cytoplasm in the cell.
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This sequence is repeated until the ribosome reaches a stop codon on the mRNA, which signals the end of protein synthesis.