ATP & ADP

ATP & ADP

ATP (Adenosine Triphosphate)
-composed of: 

Aerobic metabolism of glucose ---> 38 ATP (malate shuttle)
---> 36 ATP (G3P shuttle)
Anaerobic glycolysis --> 2 net ATP per glucose molecule
ATP can be used as energy to drive energetically unfavorable reactions.

ADP has one less phophoryl group (and has less energy than ATP).