The DNA molecule is the key for making everything in the cell.
The sequence of the nucleotides that make the DNA hold the information for the synthesis of proteins and non-coding RNAs. These two types of molecules are the key elements of the cell organisation. The proteins can be structural components of the cells, or guide the cell metabolism as enzymes and the non-coding RNA modify cell functions.
In animal cells there are two different DNA molecules, the one in the nucleus, governing the cell processes, and one in the mitochondria that hold information about the specific proteins needed for cell respiration and the production of energy in the cell. In plant cells, in addition to these two, there is also the third different DNA molecule that is in the chloroplast.
