in cell biology, protein synthesis is a core biological process balancing the loss of cellular proteins though the production of new proteins
protein synthesis involves reading information from DNA to know the sequence of amino acids needed to construct a protein, and then constructing the protein
protein synthesis can be divided into two phases: transcription and translation
transcription
transcription is the process of copying a segment of DNA into RNA
during transcription, a section of DNA encoding a protein, called a gene, is converted into a mRNA
transcription begins when an enzyme called RNA polymerase binds to the DNA at a specific region call the promoter
the DNA double helix is unwound and the RNA polymerase moves along, reading the amino acid sequence and adds corresponding nucleotides to a new mRNA chain
when the RNA polymerase reaches the end of the gene, it releases the mRNA
translation
the generated proteins is a sequence of amino acids, coded by the sequence of nucleotides in the RNA
in translation, mRNA is transported out of the nucleus and decoded in a ribosome
ribosomes have binding sites
at the binding sites, each triplet of nucleotides on the mRNA (called a codon) attract a transfer RNA (tRNA) molecule loaded with a matching triplet of nucleotides (called an anticodon) that is attached to a corresponding amino acid (following the RNA codon table)