1. 4.1 Chemical Energy and ATP KEY CONCEPT All cells need chemical energy.

2. 4.1 Chemical Energy and ATP The chemical energy used for most cell processes is carried by ATP. Molecules in food store chemical energy in their bonds. Starch molecule Glucose molecule How do we get the energy we need? Food. Is it actually the food that energized us?

3. 4.1 Chemical Energy and ATP ATP is a molecule that transfers energy from the breakdown of food molecules to cell functions. Cells require chemical energy. This energy is carried by Adenosine Triphosphate (ATP) ATP is used by cells to build molecules, move materials (active transport), etc.

4. 4.1 Chemical Energy and ATP phosphate removed –Energy is released when a phosphate group is removed, the reaction removing P releases energy. –ADP is changed back into ATP when a phosphate group is added (Cycle). ATP, which has 3 phosphates, powers cell functions by releasing the third phosphate and becoming ADP.

5. 4.1 Chemical Energy and ATP Organisms break down carbon-based molecules to produce ATP. Carbs, lipids, and proteins are broken down to make ATP. –not stored in large amounts –up to 36 ATP from one glucose molecule triphosphateadenosine diphosphate tri=3 di=2 Carbos are most commonly broken down to make ATP.

6. 4.1 Chemical Energy and ATP Fats store the most energy. –80 percent of the energy in your body –about 146 ATP from a triglyceride Proteins are least likely to be broken down to make ATP. –amino acids not usually needed for energy (protein) –about the same amount of energy as a carbohydrate Which molecules store the most energy?

7. 4.1 Chemical Energy and ATP A few types of organisms do not need sunlight and photosynthesis as a source of energy. Some organisms live in places that never get sunlight. In chemosynthesis, chemical energy is used to build carbon-based molecules. –similar to photosynthesis –uses chemical energy instead of light energy