Enzymes break up water or H2O into electrons, H+ ions, & oxygen atoms. Electrons replace the "highenergy" electrons that were lost in the electron transport chain.<span>Oxygen is released and the H+ ions are also released. - So the first one would be A. splitting of water or H2O
and the second one is B :)
</span>
True. we live in the troposphere.
No only respiration occurs