What is one characteristic of macromolecules related to energy?

Macromolecules, particularly carbohydrates, lipids, and proteins, play crucial roles in energy metabolism and storage within living organisms. One significant characteristic of macromolecules is their ability to store energy in their chemical bonds. For instance, carbohydrates like glycogen and starch serve as primary energy reserves in animals and plants, respectively. Lipids, such as fats, are highly efficient energy storage molecules, yielding more energy per gram than carbohydrates or proteins when metabolized.

This characteristic is vital as it enables organisms to maintain energy homeostasis and provide energy when immediate sources are not available. Therefore, the correct answer emphasizes the importance of macromolecules in energy storage, highlighting their role in sustaining life through energy management and reserves.