Metabolites and Macromolecules The major precursors for the formation of biomolecules are water,carbon dioxide,and three inorganic nitrogen compounds-ammonium (NH4+), nitrate (NO3),and dinitrogen (N2).Metabolic processes assimilate and transform these inorganic precursors through ever more complex levels of biomolecular order. Metabolites and Macromolecules The major precursors for the formation of biomolecules are water, carbon dioxide, and three inorganic nitrogen compounds—ammonium (NH4+), nitrate (NO3 - ), and dinitrogen (N2 ). Metabolic processes assimilate and transform these inorganic precursors through ever more complex levels of biomolecular order