Answer:
Lipids
Explanation:
Out of the four biological molecules in living systems (carbohydrate, lipids, proteins, nucleic acids), Carbohydrates and lipids have the ability to store energy in their chemical bonds. However, lipids/fats are primarily used by cells for long term storage of energy due to their ability to store more energy than any other organic biomolecule.
The high energy storing ability of lipids is attributed to the carbon bonds in their long fatty acid chain. They store energy in the covalent bonds that form between this carbon elements. The breaking down of one gram of a lipid yields 9 calories of energy, which is more than the 4 calories yielded by proteins and carbohydrates respectively
