Answer:
Carbonization is the term for the conversion of an organic substance into carbon or a carbon-containing residue through pyrolysis or destructive distillation. It is often used in organic chemistry with reference to the generation of coal gas and coal tar from raw coal.
Lipids would be the answer that you are looking for. When talking food energy it's best to speak in terms of calories. Therefore, lipids or fats offer the greatest amount of heat or energy.
Lungs, lung cells, lung tissues
