The genes for the enzymes of glycolysis
◦ are present in all metabolizing cells, and the genes for specialized proteins are expressed in all cell types.
◦ and the genes for all specialized proteins are expressed in all metabolizing cells.
◦ and the genes for all specialized proteins are expressed in all embryonic cells.
◦ are present in all metabolizing cells, but the genes for specialized proteins are expressed only in particular cell types.