Embedded in the inner membrane are proteins and complexes of molecules that are involved in the process called electron transport. The electron transport system (ETS), as it is called, accepts energy from carriers in the matrix and stores it to a form that can be used to phosphorylate ADP. Two energy carriers are known to donate energy to the ETS, namely nicotine adenine dinucleotide (NAD) and flavin adenine dinucleotide (FAD). Reduced NAD carries energy to complex I (NADH-Coenzyme Q Reductase) of the electron transport chain. FAD is a bound part of the succinate dehydrogenase complex (complex II).
HERE you will find an amazing website VIRTUAL CELL ANIMATION COLLECTION. Take a look at an electron transport chain (ETC). HERE there is another good video about ETC in mitochondria.
Useful animations are available HERE and HERE.
Some theory notes
For practice try doing these tasks
Below you will find answers
Big thanks to https://www.tamu.edu/faculty/bmiles/lectures/electrontrans.pdf, web.mnstate.edu/provost/Chem410ETSOxPhosAnswers.pdf, and web.mnstate.edu/provost/Chem410ETSOxPhosAnswers.pdf.