• Digestion: Carbohydrates are broken down into simple sugars (e.g., glucose) during digestion.
• Absorption:Glucose is absorbed into the bloodstream from the small intestine.
• Cellular Uptake:Cells take in glucose for energy or convert it into glycogen for storage.
• Glycolysis:Glucose is partially broken down in the cytoplasm, producing pyruvate and a small amount of ATP.
• Citric Acid Cycle (Krebs Cycle):Pyruvate is further broken down in the mitochondria, releasing more energy.
• Oxidative Phosphorylation: Electron transport chain generates the majority of ATP in the mitochondria.
• Glycogenesis and Glycogenolysis: Glycogen is formed from glucose when energy is abundant and broken down when energy is needed.
Protein Metabolism:
• Digestion: Proteins are broken down into amino acids during digestion.
• Absorption:Amino acids are absorbed into the bloodstream.
• Cellular Uptake: Cells use amino acids to build new proteins or for energy.
• Transamination: Amino acids undergo transamination to form different amino acids.
• Deamination: Removal of amino groups, leading to the formation of ammonia and keto acids.
• Gluconeogenesis: Some amino acids can be converted into glucose when needed.
Fat Metabolism:
• Digestion: Fats are broken down into fatty acids and glycerol during digestion.
• Absorption: Fatty acids are absorbed into the bloodstream.
• Cellular Uptake: Cells use fatty acids for energy or store them as triglycerides.
• Beta Oxidation: Fatty acids are broken down in the mitochondria to produce acetyl-CoA.
• Ketogenesis: Excess acetyl-CoA can be converted into ketone bodies during fasting or low-carbohydrate conditions.
• Lipogenesis: Formation of new fat molecules from acetyl-CoA, usually in response to an excess of glucose.
These processes are interconnected and regulated to maintain energy balance and support the diverse functions of the body.
