sentence2_structure: The energy<>stored<>in the organic molecules of food$$$The energy stored in the organic molecules of food<>comes<>from the sun<>ultimately
sentence1: Photosynthetic organisms     obtain their energy from the sun and use this energy to make food.
sentence2: The energy stored in the organic molecules of food ultimately comes from the sun.
question: The energy stored in the organic molecules of food ultimately comes from where?