Figure: A Eukaryotic Cell
Use with permission from Liliana Torres . Also at http://www.animalport.com/animal-cells.html
Nucleic acids are polymers of deoxyribonucleotides (DNA) or ribonucleotides (RNA). DNA contains the genetic code that when transcribed into RNA followed by translation of the RNA for around 22,000 protein. Only about 2% of the 3.2 billion base pairs of DNA encodes protein. The function of 80% of the remaining genome has recently been found to regulate the transcription of DNA, mostly through various types of RNA transcribed from the DNA.
The following site will show you the "life" history of nucleic acids in cells.