To a culture of growing Nostoc, as scientist adds the follow…

To a culture of growing Nostoc, as scientist adds the following radioactive elements:  nitrogen, carbon, phosphorus, and sulfur. The scientist then harvests and extracts the various macromolecules from the cells. In which macromolecules will the scientist find each of the radioactive elements? Note:  the question does not ask about structures (eg., cell walls).  It asks about macromolecules.