ABSORPTIVE STATE PRE-LECTURE
Dr. Dalay Olson Office: 3-120 Jackson Hall Office Hours Tuesday 1-3pm [email protected] WHAT HAPPENS TO FOOD BETWEEN DIGESTION AND STORAGE?
Why do we eat food in the first place?? LEARNING OBJECTIVES
1. Describe the journey of glucose, amino acids from Gut liver peripheral cells where they are used and stored. 2. Explain how glycogenesis and lipogenesis in the liver prevent large spikes of plasma glucose after a meal. 3. Compare and contrast the storage of absorbed TGL vs. TGL from the liver. 4. Describe negative feedback regulation of insulin. 5. Explain how insulin promotes Rx of absorptive state. 6. Describe the relationship btwn diabetes mellitus and hyperglycemia. METABOLISM
• Sum of chemical reactions in the body 1. Extract energy from nutrients 2. Use energy for work 3. Store excess energy • Anabolic pathways synthesize larger molecules from smaller ones • Fed state, or absorptive state • Catabolic pathways break large molecules into smaller ones • Fasted state, or postabsorptive state
© 2013 Pearson Education, Inc. ANABOLIC CATABOLIC PATHWAYS PATHWAYS
• Glycogenesis (glyco-genesis) • Glycogenolysis (glycogen-o- • Formation of glycogen lysis) • Breakdown of glycogen • Lipogenesis (lipo-genesis) • Formation of lipids • Liopolysis (lipo-lysis) • Breakdown of lipids • Gluconeogenesis (gluco- neo-genesis) • Formation of glucose “Genesis” = formation “Lysis” = breakdown INGESTED ENERGY MAY BE USED OR STORED
• Ingested biomolecules have three fates 1. Energy to do mechanical work 2. Synthesis for growth and maintenance 3. Storage as glycogen or fat • Nutrient pools are pools available for immediate use • Free fatty acids pool • Glucose pool • Amino acid pool
© 2013 Pearson Education, Inc. EXCESS ENERGY CAN BE STORED AS FAT AND GLYCOGEN
• Glycogen (glucose polymer) • Stored in liver and skeletal muscles • Rapid source of energy • Fat • Fats have more than twice the energy content of an equal amount of carbohydrate or protein • Energy in fats is harder and slower to access
© 2013 Pearson Education, Inc.