310 likes | 710 Views
Chapter 6 CELLULAR OXIDATION What Is Oxidation? Oxidation = the process of removing an electron form a molecule (e.g. Hydrogen) In the case of energy production, the electron provides the energy needed to reform ATP from ADP and P Ultimately, the H will combine with O 2 to form H 2 O
E N D
Chapter 6 CELLULAR OXIDATION
What Is Oxidation? • Oxidation = the process of removing an electron form a molecule (e.g. Hydrogen) • In the case of energy production, the electron provides the energy needed to reform ATP from ADP and P • Ultimately, the H will combine with O2 to form H2O • Oxidation involves the Krebs Cycle, Electron Transport Chain, and Beta Oxidation
Where Does Oxidation Occur? • Mitochondria (plural) • Mitochondria are located in two areas • Subsarcolemmal • Intermyofibillar • Red in color • Outer membrane • Intermembrane space • Cristea • F complexes • Inner membrane
What are the Functions of the Krebs Cycle? • An imperfect cycle • Products • CO2 • ATP • H • Which product is most important? • Why?
The Krebs Cycle • 3 CO2 • 1 ATP (GTP) • 4 NADH • 1 FADH
How Does Pyruvate Enter the Krebs Cycle? • Pyruvate Dehydrogenase (PDH) – a rate limiting enzyme • Function/Products • Pyruvate to Acetate • Add Coenzyme A • Produces Acetyl-CoA, CO2, NADH • Stimulated by NAD, ADP, CoA • Inhibited by NADH, ATP, Acetyl CoA
Actyl-CoA • Sources of Actyl-CoA • Glucose (Pyruvate) • Fatty acids • Amino acids • Combines with OAA to form citric acid
Key Enzymes • Isocitric Dehydrogenase (IDH) • The rating limiting enzyme • Inhibited by NADH • Stimulated by NAD+
What is the Function of NADH and FADH? • Transport H to Electron Transport Chain • NADH give 3 ATP for every H • FADH give 2 ATP for every H
What Happens in the Electron Transport Chain? • Inner mitochondrial membrane • Oxidation – removal of electrons (H) • Series of steps from higher to lower energy • A chemical and electrical gradient is formed
Phosphorlyation: ADP + P ATP Re-entry of H provide energy (Fig. 6-10) Linked to the formation of water Oxygen is the final electron acceptor H2O More Electron Transport Chain
GLYCOLYSIS Start with glucose
GLYCOLYSIS End with pyruvate
KREBS CYCLE Start with pyruvate being converted to Acetyl-CoA End up with… NADH/FADH CO2 ATP
ALL TOGETHER • GLYCOLYSIS • KREBS • ELECTRON TRANSPORT CHAIN
ALL TOGETHER • GLYCOLYSIS • KREBS • ELECTRON TRANSPORT CHAIN • ALL TOGETHER • GLYCOLYSIS • KREBS • ELECTRON TRANSPORT CHAIN NAD NADH Lactic Acid
Anaerobic and Aerobic • Initially, most glucose is used aerobicly • As more glucose is required, due to an increase in intensity, more NADH • If the additional NADH cannot transfer H to mitochondria, then lactate levels increase • The more O2 that is supplied to the mitochondria, the less H will be used to convert pyruvate to lactate
Oxygen Supply • Increase cardiac output • Increase heart size • Increase blood volume • Increase red blood cells • Increase capillaries • Increase myoglobin
Mitochondria and Training • Larger or more mitochondria (double) • Same activity level per mito • Higher resting metabolic rate • Stimulators of new mito: • Hypoxia • ADP • Pi
Carbon Dioxide VCO2 Oxygen LUNGS Ventilation HEART Cardiac Output MUSCLE Oxidation O2 CO2 • Energy • ATP • Kcal Carbon Dioxide Oxygen VO2
Key Topics • Using glucose/glycogen as an aerobic fuel • Fate of pyruvate • Krebs cycle • Electron transport chain • Role of oxygen • Measurement of oxygen consumption (VO2)
Assignment • By Monday, one question each from chapters 7 & 8.