Lipids (fats) that are found in things such as butter, cream and cooking oil are important because they store energy so when all the carbohydrates run out energy, all the energy that is stored in the lipids (fats) can then be used. Fats acts as a store for extra energy.
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<span>This energy gets trapped in the ATP as it converts from ADP to ATP by the addition of phosphate. There are 3 main pathways for harvesting energy from glucose: Glycolysis - begins glucose metabolism in all cells to produce 2 molecules of pyruvate. Occurs outside of mitochondria, usually in cytoplasm</span>