Metabolism

1. Metabolism

2. Metabolism • The sum of all cell activity • How cells make energy from the food we eat to conduct body processes. • The process starts with digestion.

3. TCA or Kreb’s Cycle • Tricarboxylic acid Cycle • The mechanism by which cells convert food metabolites into ATP (adenosine triphosphate). • ATP is an organic molecule that stores and releases chemical energy from cell reactions. • This process happens in the mitochondria of our cells.

4. Food Metabolites • ALL the food we eat breaks down into these constituents (or metabolites): • Carbohydrate • Lipid • Protein • Vitamins • Minerals • Water • Fiber

5. Energy Yielding Nutrients • Only carbohydrates, fat and protein are used as an energy source. • These nutrients are broken down to basic metabolites by the digestion process. • Carbohydrate yields glucose • Fats yield glycerol and fatty acids • Proteins yield amino acids

7. Other Nutrients • Vitamins and Minerals act as coenzymes that assist in the breakdown of the energy yielding nutrients. • Water acts as a solvent in which metabolism occurs.

8. Metabolism: The beginning • Cells receive glucose, glycerol, fatty acids and amino acids via the blood stream. • The cells take these metabolites convert them into two substances: • Pyruvate (a three carbon substance) • Acetyl CoA (a two carbon substance joined by a coenzyme made from the vitamin panothenic acid. • Enzymes are need for metabolism to occur

14. Once all metabolites are converted to Acetyl CoA, they can do one of the following:1. Enter the TCA cycle and eventually generate ATP2. it can be used to synthesize fats.