Which types of reactions occur along the two electron transport chains?

Redox reaction occur along the two electron transport chains.

Explanation:

In redox type of chemical reaction, the oxidation state of the atoms is changed due to the transfer of electrons between the chemical reactants. One of the species is oxidized whereas the next species are reduced. The electron gaining species undergoes reduction but the species that donate the electron gets oxidized. In a redox reaction, the process of oxidation and reduction occurs simultaneously. In redox reaction, oxidation of one species means the reduction of the next species that shares electrons.