Modern classical music is music written in the 20th century and beyond. Although much of it draws heavily on earlier forms, modern composers also experimented with rejection of long-held ideas; notably, Arnold Schoenberg questioned the traditional notions of harmony with his twelve-tone system[?], and John Cage questioned the very definition of music with his use of chance and found sounds.
... + 6CO2 + light → C6H12O6 (glucose) + 6O2
In simple English terms, this is carbon dioxide plus water plus light (energy) yields oxygen plus sugar. In animal ...