DNA carries the cell’s genetic information; however, it cannot leave the . Because of this, it copies part of its nucleotide sequence into a complementary copy of during the process called . During this process, Polymerase separates the DNA strands. It then uses one strand of DNA as the from which nucleotides are assembled into a strand of RNA. Each three letter sequence on the mRNA is called a . The start codon is and the three stop codons are , , . Once the mRNA leaves the nucleus it goes to the to prepare for protein synthesis which is called . During this process, a molecule brings the to the ribosome. The amino acids are hooked together by bonds. The tRNA is able to match up to the mRNA by its . When the stop is reached, the chain is released into the .