Final answer:
Glucose is the primary food molecule that provides energy for animal cells, used to produce ATP which fuels cellular functions. It is obtained from the breakdown of digestible carbohydrates and can be stored as glycogen or converted into fat.
Step-by-step explanation:
The food molecule whose breakdown generates most of the energy for a majority of animal cells is glucose. Glucose, a simple sugar, is the primary fuel that cells use to produce adenosine triphosphate (ATP), which transfers energy to other cellular reactions. Energy from glucose breakdown is crucial for all cell functions, including cellular respiration, movement, synthesis of new molecules, and transport of molecules across cell membranes.
Within the catabolic chemical reactions of digestion, carbohydrates, especially glucose obtained from plant-based foods through photosynthesis, are converted to a usable form of energy for cells. Excess glucose is stored in the liver and skeletal muscles as glycogen or is transformed into fat for later use. Hence, glucose is the fundamental food molecule that channels solar energy, via plants, to animals, connecting the ecosystem's energy flow.