Final answer:
Energy can be converted but not created or destroyed, adhering to the law of conservation of energy. This is also an expression of the first law of thermodynamics and applies universally in both living and non-living systems.
Step-by-step explanation:
Energy cannot be created or destroyed; it can be converted from one form to another. This statement is a fundamental concept known as the law of conservation of energy. According to this law, the total amount of energy in the universe remains constant, meaning that during any chemical or physical change, the energy can be neither created nor destroyed. Instead, it is always preserved, merely undergoing a transformation from one form to another. For instance, electrical energy can be converted to thermal energy in a toaster, or kinetic energy can be converted to potential energy in a roller coaster.
This principle is also a version of the first law of thermodynamics, which applies to all forms of energy. Whether in living systems, non-living systems, or combinations of both, matter and energy are consistently subject to this law. The conservation of energy is a constraint that ensures that after any process, the amount of energy remains unchanged, just like exchanging quarters for dollar bills doesn't alter the total amount of money you have.