Genes carry the information necessary to synthesize proteins, which are manufactured in the organelles surrounding the nucleus of a cell. Specialized sections of RNA transcribe the instructions from the genes and carry them out to the cell for production.
DNA is a large structure that is made of one long sequence of nucleotides, linear stretches called genes. The effect each gene has on the chemistry of the cell is determined by the exact sequence of nucleotides in its makeup. Sections of RNA, known as "messenger" or mRNA, mold themselves to individual genes on the chromosome and carry a negative impression of the gene being read out of the nucleus. There, in special structures called organelles, strands of mRNA make contact with other strands of RNA, known as "transcription" or tRNA.
Each strand of tRNA carries organic molecules called amino acids, which it then slots into place along an ever-growing chain, the shape of which is determined by the shape of the mRNA. When the full sequence of amino acids has been laid down, the chain is released and begins to fold in three dimensions. The three-dimensional shape the chain adopts is a protein, and its function is dependent on its geometry. Its geometry is directly determined by the linear sequence of amino acids along its length, which is, in turn, coded for in the gene that began the process.