After consuming the food,we will digest food in the stomach.The main nutrition will be absorbed into small intestine through 【小肠壁的绒毛】(专业术语我不会啊)into our circulatory system and delivered to every cell in our body.The cytomembrane takes charge of the exchange of materials,which helps beneficial materials move into the cell.The mitochondria in cytoplasm will decompose the organics and release energy.Such is how we get our energy from consumption. 本人没怎么学过生物啊,当初SAT也没考生物,所以中间那个“小肠壁的绒毛”不晓得怎么翻.