Protein Synthesis SummaryProtein Synthesis occurs because DNA molecules are too big to get through the nuclear pores. Therefore, there has to be another way to get the DNA code out of the nucleus. In transcription, the first stage of protein synthesis, RNA polymerase splits the DNA strand and uses one strand of the DNA as a template. As it splits the DNA, it synthesizes an RNA strand that is complementary to the template strand. Once RNA polymerase goes through, the DNA strand goes back together. The RNA strand that is synthesized in this stage is a mRNA strand (messenger RNA). There are three differences between DNA and RNA. DNA has deoxyribose and RNA has ribose, DNA has two strands and RNA has one, and DNA’s bases are Adenine-Thymine and Cytosine-Guanine, where RNA’s bases are Adenine-Uracil and Cytosine-Guanine. Once the mRNA strand is made, it is small enough to fit through the nuclear pores. It goes through the nuclear pores into the cytoplasm where it meets a ribosome. This stage is called translation. In translation, tRNA and anti-codons bind to the mRNA strand and fall off. When they fall off, they leave an amino acid which forms a peptide bond with the other amino acids. This process continues until it reaches the “stop” codon. After it reaches the “stop” codon, the final protein has been made. It does not have a specific function until it is formed into a three dimensional shape. This is the end of Protein Synthesis.