Where is the frog liver and what is the purpose of this structure?

Choose the molecule that is described by each phrase. energy used during long activities:

~~16. while watching a special on animals, brianna discovers that hares tend to lose heat through their ears. based on this and what is known about surface-to-volume ratios, propose an explanation as to why hares that live in hot climates (such as the desert) have large, extended ears

What do all celular activities in living organisms use as a source of energy?