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Well, protein synthesis is the name of the process. Perhaps you could also say 'gene expression' because in building the proteins, the DNA tells the cell which proteins to make, how to make them, and that affects our cellular metabolic functions as well as our phenotypes because some proteins are structural. The two phases are transcription, which is when a molecule of mRNA (messenger RNA) reads, or transcribes, a specific codon on a DNA molecule. The codon is transcribed in reverse. Then, the mRNA goes to the ribosome and bonds with a molecule of tRNA (transfer RNA), and this is called translation because the tRNA translates the codon on the mRNA in reverse, returning the original order of the DNA code. Each codon, or triplet, of nucleotide bases codes for one amino acid in the protein molecule, and it takes many hundreds of even thousands of amino acids to make a particular protein.
Let's look at this process, using one codon. Adenine binds with thymine (in DNA) and uracil (in RNA); guanine always bonds with cytosine. This is because these base pairs fit together like puzzle pieces, and only guanine fits with cytosine, only uracil or thymine with adenine.
Now..suppose our DNA molecule has the following triplet along its length, and this is needed to code for an amino acid in a specific protein molecule.
DNA codon:
T
C
C
A molecule of mRNA will come in and bond to this codon in a mirror image, so the mRNA molecule that fits will be the one with the bases AGG on it. THEN, this mRNA molecule, coded for AGG, goes to the ribosome where a matching tRNA molecule will come in and bond, again in reverse. This code will be UCC, which matches the DNA code (remember, uracil is the RNA equivalent of thymine, so U in RNA is the same as T in DNA.)
Then, the tRNA molecule will go and get the amino acid it is coded for (again, the amino acids fit on the tRNA codes like puzzle pieces, so the codon is important because it is important that the proper amino acid be brought back to the ribosome), and enzymes help the tRNA molecule attach this amino acid in the proper place in the growing chain of the polypeptide, which will become a functional protein once its synthesis is complete.
I hope this helps!
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