Describe how protein is made in the cell.

The sequence of bases in the DNA determines the exact order of the amino acids in the protein. Every three adjacent bases on the DNA strand, called a codon, encodes a particular amino acid. The DNA cannot leave the nucleus because it is double stranded, so a matching copy of the DNA base sequence is transcribed into mRNA (messenger RNA). The base sequence of mRNA contains codons specifying the same amino acid sequence, specified by the DNA of the gene.The mRNA is able to move out of the nucleus into the cytoplasm, as it is single stranded and mobile. It attaches to the ribosome, which is the site of translation. During translation, the ribosome reads the sequence while moving along the mRNA strand and uses tRNA (transfer RNA) molecules to synthesise the amino acid sequence the mRNA encodes. Each tRNA molecule has an anticodon, which is a group of three bases that pair up with a specific codon on the mRNA. They are also attached to an amino acid that corresponds to the specific codon. Therefore, each tRNA delivers a different amino acid to the ribosome. On the ribosome, the amino acids become chemically linked together by strong bonds to form the polypeptide chain/protein. Therefore, the original amino acid sequence encoded on the DNA, is synthesised in the cytoplasm of the cell.