Verified answer

Answer:

Humans obtain energy from three classes of fuel molecules: carbohydrates, lipids, and proteins. The potential chemical energy of these molecules is transformed into other forms, such as thermal, kinetic, and other chemical forms.

Explanation:

Foods contain a lot of stored chemical energy; when you eat, your body breaks down these foods into smaller components and absorbs them to use as fuel. Energy comes from the three main nutrients carbohydrates, protein, and fats, with carbohydrates being the most important energy source.