Due to the definition of the central dogma, another way of putting it is that the central dogma follows the flow of information from DNA to protein.
Unlike other ways of reproduction, sexual reproduction provides variation through inheriting various genes. This variation is essential for adaptation as it would not just create a copy of the original life form, but rather a different unique life form that could adapt to something, and then have it's own offspring with the adapted trait.
All the cells in a person's body have the same DNA and the same genes. However, the difference between cells in different tissues and organs is that the "expression" of the genes differs between cells. ... For example, liver cells have different proteins than skin cells, even though their DNA is the same......this is a google search i hope it helps
