What energy is used for long activitys?

ATP is chemical, and that is an Aerobic activity.

an active site is a region that is present on an enzyme where the reactants or the substrate molecules we can say bind and experience a chemical reaction. the substrate is basically a reactant whose concentration is changing and that is converting into a product after binding at the active site of an enzyme

all matter is made up of atoms

in any element all atoms are the same

elements in a compound are always in a constant ratio: apex