Final answer:
The original source of energy in the food you eat is the sun, which is used by plants through photosynthesis to produce glucose.
Step-by-step explanation:
Original Source of Energy in Food
The original source of energy in the food you eat is the sun. Through the process of photosynthesis, plants use sunlight to convert carbon dioxide and water into glucose, a form of sugar that serves as their energy source. When you consume plants or plant-eating animals, you obtain this energy indirectly from the sun.
For example, when you eat a salad with lettuce, the lettuce originally obtained its energy from sunlight, and you get that energy when you consume the lettuce.
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