01/29/2011 20:03:42 true false false 32 07 false 1.1 false false false default_0.swf 12 Slide1 1 NS 315Unit 4: Carbohydrate Metabolism Dr. Rebekah S. Marsh Kaplan University 720 540 false false 14 slide1.swf Slide2 1 Unit 7: Exercise paper Four hours ago, I ate 3 oz of baked chicken marinated in 1 tsp olive oil and other spices, 1 cup rice and ½ cup beans, 2 cups salad (romaine lettuce, carrots, onions and radishes) with 2 tablespoons ranch dressing and 1 cup of skim milk. Now, I am going to run for 45 minutes and will lift weights for another 30 minutes DUE: by EOD Tuesday 03/22/2011 Are these activities considered aerobic, anaerobic or a combination of both? And why do you believe so based on the scenario above? Based on the meal plan above, what foods contain carbohydrates, proteins and fats? How are carbohydrates, proteins and fats digested and absorbed? Which main pathway is utilized (glycolysis, gluconeogenesis, beta oxidation) when first starting to work out? What macronutrient does this pathway use and what are the end products? Please explain beta oxidation and gluconeogenesis: what macronutrients they are utilizing, what the end products are and why they are needed while working out? 720 540 false false 14 slide2.swf Slide3 1 Introduction to Carbohydrate Metabolism 720 540 false false 14 slide3.swf Slide4 1 Key Terms Anabolism: Assembly of complex organic molecules Catabolism: Degradation of complex molecules Heterotrophs: Synthesize their organic metabolites only from other organic compounds, which they consume 720 540 false false 14 slide4.swf Slide5 1 Key Terms Intermediary Metabolism: All reactions concerned with storing and generating metabolic energy and with using that energy in biosynthesis of low molecular weight compounds Energy Metabolism: Pathways that store or generate metabolic energy 720 540 false false 14 slide5.swf Slide6 1 Overview of Metabolism 720 540 false false 14 slide6.swf Slide7 1 Three Stages of Metabolism ncbi.nlm.nih.gov 720 540 false false 14 slide7.swf Slide8 1 The Major Metabolic Pathways http://staff.jccc.net/PDECELL/cellresp/simpleover.gif 720 540 false false 14 slide8.swf Slide9 1 Biosynthesis & Degradative Pathways 720 540 false false 14 slide9.swf Slide10 1 Carbohydrate Metabolism:Glycolysis and Gluconeogenesis 720 540 false false 14 slide10.swf Slide11 1111 1 Key Terms Glycolysis: central pathway for the catabolism of carbohydrates; occurs in most organs Glyconeogenesis: Biosynthesis of new glucose; occurs mainly in liver Glycogenesis: group of enzymatic reactions leading to the formation of glycogen Glycogenolysis: group of enzymatic reactions that use stored glycogen to form glucose 720 540 false false 14 slide11.swf Slide12 1212 1 Key Terms (continued) Pyruvate: final 3 carbon molecule of glycolysis, involved in the Krebs cycle which facilitates energy production Adenosine diphosphate (ADP) /Adenosine triphosphate (ATP): energy storing molecule used by an organism on a daily basis Aerobic: in the presence of oxygen Anaerobic: no presence of oxygen 720 540 false false 14 slide12.swf Slide13 1 Glycolysis Animation Please review the website for an animated description of glycolysis pathway and we will discuss it in 5 minutes http://www.youtube.com/watch?v=x-stLxqPt6E Other good sites to review Glycolysis: http://www.cliffsnotes.com/WileyCDA/CliffsReviewTopic/Introduction-to-Glycolysis.topicArticleId-24998,articleId-24980.html http://www.dnatube.com/video/2338/Glycolysis 720 540 false false 14 slide13.swf Slide14 1 Glycolysis http://www.accessexcellence.org/RC/VL/GG/ecb/ecb_images/13_01Glycolysis-Steps_1-5.jpg 720 540 false false 14 slide14.swf Slide15 15 1 Fates of Pyruvate Under aerobic conditions Under anaerobic conditions In most aerobic organisms, pyruvate continues in the formation of Acetyl CoA and NADH that follows into the Krebs cycle and ETC Under anaerobic conditions, such as during exercise or in red blood cells (no mitochondria), pyruvate is reduced to lactate by lactate dehydrogenase producing NAD for glycolysis 720 540 false false 14 slide15.swf Slide16 1616 1 Pathways during Glycolysis Aerobic- with oxygen The main energy releasing pathway in most human cells Continues in the mitochondrion where oxygen serves as the final electron receptor 1 glucose + 6 oxygen  6 carbon dioxide +6 water 36 or 38 ATPs are produced (total after all cycles: glycolysis, krebs and ETC) Anaerobic- without oxygen Fermentation pathway and anaerobic electron transport- many bacteria and humans, when oxygen is limited, use this pathway Ends in the cytoplasm where other substances besides oxygen is the final electron receptor Only 2 ATP are produced 720 540 false false 14 slide16.swf Slide17 1 Gluconeogenesis http://themedicalbiochemistrypage.org/images/gluconeogenesis.jpg 720 540 false false 14 slide17.swf Slide18 1818 1 Gluconeogenesis Synthesis of glucose from 3-4 carbon precursors is a reversal of glycolysis 3 reactions in glycolysis are essentially irreversible, thus they are bypassed in gluconeogenesis: Hexokinase (1) Phosphofructokinase (3) Pyruvate Kinase (10) Share 7 of the 10 steps in glycolysis 720 540 false false 14 slide18.swf Slide19 1919 1 Fed state Cytoplasm All cells Fasting state Cytoplasm Liver mostly, but also kidney Glycolysis vs Gluconeogenesis 720 540 false false 14 slide19.swf Slide20 1 Carbohydrate Metabolism:Krebs Cycle and Electron Transport Chain 720 540 false false 14 slide20.swf Slide21 21 1 Definitions Krebs cycle - series of enzymatic reactions in aerobic organisms involving oxidative metabolism of acetyl units and producing high-energy phosphate compounds, which serve as the main source of cellular energy Electron Transport Chain (ETC) - Composed of mitochondrial enzymes that transfers electrons from one transport to another, resulting in the driving force for the formation of ATP Oxidative phosphorylation - Process occurring in the cell, which produce energy and synthesizes ATP 720 540 false false 14 slide21.swf Slide22 1 Definitions NAD/NADPH: Reducing agent in several anabolic reactions such as lipid and nucleic acid FAD/FADH: Reducing agent in several anabolic reactions such as lipid 720 540 false false 14 slide22.swf Slide23 1 Krebs Cycle Also known as the citric acid cycle or tricarboxylic acid (TCA) cycle Under aerobic conditions pyruvate enters the mitochondria MATRIX and is oxidized to Acetyl CoA which enters the Krebs cycle Krebs cycle can occur after glycolysis, after Beta oxidation or protein degradation to provide energy for cellular respiration Equation for Krebs cycle with the beginning products and the ending. 8 steps involved 720 540 false false 14 slide23.swf Slide24 1 Krebs Cycle Please go to: http://highered.mcgraw-hill.com/sites/0072507470/student_view0/chapter25/animation__how_the_krebs_cycle_works__quiz_1_.html and we will discuss the krebs cycle after the animated movie. Other sites for the Krebs Cycle: http://www.dnatube.com/video/2354/Electron-Transport-Chain http://www.elmhurst.edu/~chm/vchembook/596electransport.html 720 540 false false 14 slide24.swf Slide25 1 Krebs Cycle (TCA) http://image.tutorvista.com/content/respiration/krebs-cycle.jpeg 720 540 false false 14 slide25.swf Slide26 1 Summary TCA Occurs in the mitochondrial matrix Uses acetyl CoA to produce: 3 NADH, 1 FADH, 1 GTP, 2Co2 Produce intermediates for biosynthetic pathways such as amino acid synthesis, gluconeogenesis, pyrimidine synthesis, phorphyrin synthesis, fatty acid synthesis, isoprenoid synthesis. 720 540 false false 14 slide26.swf Slide27 1 Electron Transport Chain (ETC) Final pathway by which electrons generated from oxidation of carbs, protein and fatty acids, are ultimately transferred to O2 to produce H2O Located in the inner mitochondrial membrane Electrons travel down the chain, pumping protons into the intermembrane space creating the driving force to produce ATP in a process called oxidative phosphorylation There are 4 complexes that comprise the ETC 720 540 false false 14 slide27.swf Slide28 1 Electron Transport Chain Please go to: http://www.brookscole.com/chemistry_d/templates/student_resources/shared_resources/animations/oxidative/oxidativephosphorylation.html and we will discuss about the ETC after the animated film. Other help link to explain the ETC: http://www.stolaf.edu/people/giannini/flashanimat/metabolism/mido%20e%20transport.swf http://vcell.ndsu.edu/animations/etc/movie.htm 720 540 false false 14 slide28.swf Slide29 1 Electron Transport Chain http://vcell.ndsu.nodak.edu/animations/etc/Stills/0917.jpg 720 540 false false 14 slide29.swf Slide30 1 Summary ETC Reduced electron carriers NADH & FADH2 reduce O2 to H2O via the ETC. The energy released creates a proton gradient across the inner mitochondrial membrane. The protons flow down this concentration gradient back across the inner mitochondrial membrane through the ATP Synthase. The driving force makes this enzyme rotate and this conformation generates enough energy to produce ATP. Oxidation of NADH to NAD+ pumps 3 protons which charges the electrochemical gradient with enough potential to generate 3 ATPs. Oxidation of FADH2 to FAD+ pumps 2 protons which charges the electrochemical gradient with enough potential to generate 2 ATPs. 720 540 false false 14 slide30.swf Slide31 1 Oxidative Phosphorylation http://stevebambas.com/images/AP%20220%20ox%20phosph.jpg 720 540 false false 14 slide31.swf Slide32 1 References Introduction to Carbohydrate Metabolism Mathews C & Van Holde K. (1990). Biochemistry. Redwood City: The Benjamin/Cummings Carbohydrate Metabolism King, M (2010). Digestion of Dietary Carbohydrates. Retrieved on May 13, 2010 from http://themedicalbiochemistrypage.org/glycolysis.html Hardy, J (2003). Gluconeogenesis. Retrieved on May 13, 2010 from http://www.elmhurst.edu/~chm/vchembook/604glycogenesis.html Campbell, Neil A. (2005) AP Edition Biology. 7th. San Francisco, CA: Pearson Benjamin Cummings Carbohydrate Metabolism: Krebs Cycle and Electron Transport Chain Phases of the Krebs Cycle (N.D.) Retrieved on May 13, 2010 from http://incolor.inebraska.com/mcanaday/Krebs%20Phases.htm Electron Transport Chain (N.D.) Retrieved on May 13, 2010 from http://vcell.ndsu.edu/animations/etc/movie.htm Campbell, Neil A. (2005) AP Edition Biology. 7th. San Francisco, CA: Pearson Benjamin Cummings 720 540 false false 14 slide32.swf