[methyl-14c]pyruvate was administered to isolated liver cells in the presence of sufficient malonate to block succinate dehydrogenase completely. after a time, isocitrate was isolated and found to contain label in both carbon 2 and carbon 4:

Are you asking about a street map usage  if so here is your answer  a street map for a very limited area could simply be a bit map or a .jpg image.  but a more general map would probably store the streets as vectors.  but you shouldn't assume that there is one way to do it

C) to ensure each new cell has an exact copy of the dna