Prokaryotic cells are simple, ancient cells without a nucleus. Eukaryotic cells are more complex and have a nucleus.
By looking for promoters that are binding sites for RNA polymerase. It's an open reading frame and introns as well as exons
Organism-population-community-ecosystem-biome in that order
I guess its DNA. DNA is the information code of the cell
The six most common elements found in living organisms are carbon, hydrogen, oxygen, nitrogen, phosphorus, and sulfur.