proteins
u have to know that proteins are synthesized from basic units called amino acids. (think small Lego blocks forming a huge structure)
the process is called condensation.
there are 20 essential amino acids which we require for our daily body use. these amino acids molecular makeup COULD consist of those elements which you mentioned in your question.
hydrogen, carbon, oxygen and nitrogen elements are ALWAYS present in all amino acids. certain types of amino acids consist of phosphorus or even sulfur elements.
