Answer: NADH and FADH2
Explanation:
The formation of adenosine triphosphte requires oxidative phosphorylation and electron transport chain . Before these two processes the energy is stored in the form of NADH and FADH2.
The formation of ATP molecules takes place when the electrons are passed on to the NADH and FADH2 molecules.
Hence, before the process of oxidative phosphorylation and electron transport chain the energy in the glucose is in the form of NADH and FADH2 molecules.