330 likes | 412 Views
Please put your test corrections in the appropriate file on the table by the door. (Please staple your corrections to your test packet.) Also, please get your lab notebook. This week…. MON: Finish Ch. 9 TUE: Case Study (Day One) & Lab Intro WED: Lab
E N D
Please put your test corrections in the appropriate file on the table by the door. (Please staple your corrections to your test packet.)Also, please get your lab notebook.
This week… • MON: Finish Ch. 9 • TUE: Case Study (Day One) & Lab Intro • WED: Lab • THU: Case Study (Day Two) & Lab Wrap-Up • *Your Osmosis Lab & Enzyme Lab are graded and in PowerSchool. *I’ll be working on grading your FRQs this week.
Chapter 9: Cellular Respiration: Harvesting Chemical Energy Light energy ECOSYSTEM Photosynthesisin chloroplasts Organicmolecules + O2 CO2 + H2O Cellular respirationin mitochondria ATP powers most cellular work Heatenergy • Why is respiration important? • Consumption of food & oxygen to produce CO2, water & energy • C6H12O6 + 6O2 6CO2 + 6H2O + energy (ATP + heat)
Chapter 9: Cellular Respiration: Harvesting Chemical Energy • Why is respiration important? • Consumption of food & oxygen to produce CO2, water & energy • C6H12O6 + 6O2 6CO2 + 6H2O + energy (ATP + heat) • Exergonic (releases lots of energy… -686 kcal/mol) • All foods can be metabolized as fuel (carbs, proteins, fats)
Chapter 9: Cellular Respiration: Harvesting Chemical Energy • Why is respiration important? • What are redox rxns? • Reduction & oxidation • LEO says GER • Loss of Electrons – Oxidation : Gain of Electrons – Reduction • Hint: electrons move with H atoms…H = e- + H+ • ┌----oxidation-----┐ • C6H12O6 + 6O2 6CO2 + 6H2O + energy (ATP + heat) • └----reduction----┘ • ENERGY COUPLING!!! • (Oxidation is exergonic…reduction is endergonic)
Chapter 9: Cellular Respiration: Harvesting Chemical Energy • Why is respiration important? • What are redox rxns? • What are the 3 main steps of respiration? • Glycolysis • Citric Acid Cycle (Krebs Cycle) • Oxidative Phosphorylation • Electron Transport Chain (ETC) • Chemiosmosis
Chapter 9: Cellular Respiration: Harvesting Chemical Energy Electrons carried via NADH Electrons carried via NADH and FADH2 Oxidativephosphorylation:electron transportandchemiosmosis Citric acid cycle Glycolysis Glucose Pyruvate Mitochondrion ATP ATP ATP Substrate-level phosphorylation Oxidative phosphorylation Substrate-level phosphorylation
Chapter 9: Cellular Respiration: Harvesting Chemical Energy • Why is respiration important? • What are redox rxns? • What are the 3 main steps of respiration? • What happens during glycolysis? • Glucose (6-C) is split in the cytosol into two 3-C pyruvate molecules • 10 steps • NO oxygen needed
Chapter 9: Cellular Respiration: Harvesting Chemical Energy Glycolysis Oxidativephosphorylation Citricacidcycle ATP ATP ATP Energy investment phase Glucose used 2 ATP 2 ADP + 2 P Energy payoff phase formed 4 ADP + 4 4 ATP P + 2 H+ 2 NAD+ + 4 e- + 4 H + 2 NADH 2 Pyruvate + 2 H2O Glucose 2 Pyruvate + 2 H2O 4 ATP formed – 2 ATP used 2 ATP + 2 H+ 2 NAD+ + 4 e– + 4 H + 2 NADH
Chapter 9: Cellular Respiration: Harvesting Chemical Energy Enzyme Enzyme ADP P Substrate + ATP Product • Why is respiration important? • What are redox rxns? • What are the 3 main steps of respiration? • What happens during glycolysis? • How is the ATP made in glycolysis? • Substrate-level phosphorylation – ATP produced from the transfer of a phosphate group from a substrate to ADP • ATP made one at a time
Chapter 9: Cellular Respiration: Harvesting Chemical Energy • Why is respiration important? • What are redox rxns? • What are the 3 main steps of respiration? • What happens during glycolysis? • How is the ATP made? • How do electrons get from glucose to O2? • NAD+ - nicotinamide adenine dinucleotide • Coenzyme (form of niacin…a vitamin!) • Accepts 2 e- and a H+ • NADH and H+ will be very important later in the respiration reaction, as they participate in more ATP formation!
Chapter 9: Cellular Respiration: Harvesting Chemical Energy 2 e– + 2 H+ 2 e– + H+ NAD+ NADH H+ H Dehydrogenase O O H H Reduction of NAD+ + + H+ 2[H] C NH2 NH2 C (from food) Oxidation of NADH N N+ Nicotinamide(reduced form) Nicotinamide(oxidized form) CH2 O O O O– P O H H OH O O– HO P NH2 HO CH2 O N N H N H N O H H HO OH
Chapter 9: Cellular Respiration: Harvesting Chemical Energy • Why is respiration important? • What are redox rxns? • What are the 3 main steps of respiration? • What happens during glycolysis? • How is the ATP made? • How do electrons get from glucose to O2? • How does pyruvate get into the mitochondria for the Krebs Cycle? • Active transport across membrane • 3 step process
Chapter 9: Cellular Respiration: Harvesting Chemical Energy CYTOSOL MITOCHONDRION NAD+ NADH + H+ O– CoA S 2 C O C O C O CH3 1 3 CH3 Acetyl CoA Pyruvate CO2 Coenzyme A Transport protein
Chapter 9: Cellular Respiration: Harvesting Chemical Energy • Why is respiration important? • What are redox rxns? • What are the 3 main steps of respiration? • What happens during glycolysis? • How is the ATP made? • How do electrons get from glucose to O2? • How does pyruvate get into the mitochondria for the Krebs Cycle? • What happens during the Citric Acid Cycle? • Mitochondrial matrix • 8 steps • “Spins" 2X per glucose (1X for each pyruvate)
Chapter 9: Cellular Respiration: Harvesting Chemical Energy Pyruvate(from glycolysis,2 molecules per glucose) Glycolysis Citricacidcycle Oxidativephosphorylation ATP ATP ATP CO2 NAD+ CoA NADH + H+ Acetyl CoA CoA CoA Citricacidcycle 2 CO2 3 NAD+ FADH2 FAD 3 NADH + 3 H+ ADP + Pi ATP
Chapter 9: Cellular Respiration: Harvesting Chemical Energy • Why is respiration important? • What are redox rxns? • What are the 3 main steps of respiration? • What happens during glycolysis? • How is the ATP made? • How do electrons get from glucose to O2? • How does pyruvate get into the mitochondria for the Krebs Cycle? • What happens during the Citric Acid Cycle? • How many ATP so far? • 4 total, 2 from glycolysis & 2 from Krebs Cycle • ALL from substrate-level phosphorylation
Chapter 9: Cellular Respiration: Harvesting Chemical Energy • Why is respiration important? • What are redox rxns? • What are the 3 main steps of respiration? • What happens during glycolysis? • How is the ATP made? • How do electrons get from glucose to O2? • How does pyruvate get into the mitochondria for the Krebs Cycle? • What happens during the Citric Acid Cycle? • How many ATP so far? • How many electron carriers so far? - 10 NADH - 2 FADH2
Chapter 9: Cellular Respiration: Harvesting Chemical Energy • Why is respiration important? • What are redox rxns? • What are the 3 main steps of respiration? • What happens during glycolysis? • How is the ATP made? • How do electrons get from glucose to O2? • How does pyruvate get into the mitochondria for the Krebs Cycle? • What happens during the Citric Acid Cycle? • How many ATP so far? • How many electron carriers so far? • What happens during electron transport? - rxns in inner mitochondrial membrane - electrons flow from electron carriers to electronegative O2 - many SMALL steps instead of one BIG step 12. Why do electron carriers NEED to “break the fall?”
Chapter 9: Cellular Respiration: Harvesting Chemical Energy H2 + 1/2 O2 2 H 1/2 O2 + (from food via NADH) Controlled release of energy for synthesis ofATP 2 H+ + 2 e– ATP Explosiverelease ofheat and lightenergy ATP Free energy, G Free energy, G Electron transport chain ATP 2 e– 1/2 O2 2 H+ H2O H2O (b) Cellular respiration (a) Uncontrolled reaction
Citircacidcycle Glycolysis Oxidativephosphorylation ATP ATP ATP NADH 50 FADH2 Multiproteincomplexes I 40 FAD FMN II Fe•S Fe•S O III Cyt b 30 Fe•S Cyt c1 IV Cyt c Free energy (G) relative to O2 (kcl/mol) Cyt a Cyt a3 20 10 0 O2 2 H + + 12 H2O Figure 9.13 Free-energy change during electron transport
Chapter 9: Cellular Respiration: Harvesting Chemical Energy • Why is respiration important? • What are redox rxns? • What are the 3 main steps of respiration? • What happens during glycolysis? • How is the ATP made? • How do electrons get from glucose to O2? • How does pyruvate get into the mitochondria for the Krebs Cycle? • What happens during the Citric Acid Cycle? • How many ATP so far? • How many electron carriers so far? • What happens during electron transport? • Why do electrons NEED to “break the fall?” • How is ATP made during chemiosmosis?
INTERMEMBRANE SPACE A rotor within the membrane spins clockwise whenH+ flows pastit down the H+ gradient. H+ H+ H+ H+ H+ H+ A stator anchoredin the membraneholds the knobstationary. H+ A rod (or “stalk”)extending into the knob alsospins, activatingcatalytic sites inthe knob. Three catalytic sites in the stationary knobjoin inorganic Phosphate to ADPto make ATP. H+ ADP + ATP P i MITOCHONDRIAL MATRIX Figure 9.14 ATP synthase, a molecular mill
Inner Mitochondrial membrane Oxidative phosphorylation electron transport and chemiosmosis Citircacidcycle Glycolysis ATP ATP ATP H+ H+ H+ H+ Cyt c Protein complex of electron carners Intermembrane space Q IV I III ATP synthase Inner mitochondrial membrane II H2O FADH2 2 H+ + 1/2 O2 FAD+ NADH NAD+ ATP ADP + P i (Carrying electrons from food) H+ Mitochondrial matrix Chemiosmosis ATP synthesis powered by the flow Of H+ back across the membrane Electron transport chain Electron transport and pumping of protons (H+), which create an H+ gradient across the membrane Oxidative phosphorylation Figure 9.15 Chemiosmosis couples the electron transport chain to ATP synthesis 1 NADH = 3 ATP (new research indicates 2.5 ATP) 1 FADH2= 2 ATP (new research indicates 1.5 ATP)
Electron shuttles span membrane MITOCHONDRION CYTOSOL 2 NADH or 2 FADH2 2 NADH 2 NADH 2 FADH2 6 NADH Glycolysis Oxidative phosphorylation: electron transport and chemiosmosis Citric acid cycle 2 Acetyl CoA 2 Pyruvate Glucose + 2 ATP + 2 ATP + about 32 or 34 ATP by oxidative phosphorylation, depending on which shuttle transports electrons from NADH in cytosol by substrate-level phosphorylation by substrate-level phosphorylation About 36 or 38 ATP Maximum per glucose: Figure 9.16 ATP yield per molecule of glucose at each stage of cellular respiration
Figure 9.16 ATP yield per molecule of glucose at each stage of cellular respiration (UPDATED)
Chapter 9: Cellular Respiration: Harvesting Chemical Energy • Why is respiration important? • What are redox rxns? • What are the 3 main steps of respiration? • What happens during glycolysis? • How is the ATP made? • How do electrons get from glucose to O2? • How does pyruvate get into the mitochondria for the Krebs Cycle? • What happens during the Citric Acid Cycle? • How many ATP so far? • How many electron carriers so far? • What happens during electron transport? • Why do electrons NEED to “break the fall?” • How is ATP made during chemiosmosis? • What happens when there is no O2? - anaerobic respiration (fermentation)
Glucose CYTOSOL Pyruvate No O2 present Fermentation O2 present Cellular respiration MITOCHONDRION Ethanol or lactate Acetyl CoA Citric acid cycle Figure 9.18 Pyruvate as a key juncture in catabolism
Pi 2 ATP 2 ADP + 2 O– C O C O Glucose Glycolysis CH3 2 Pyruvate 2 NADH 2 NAD+ 2 CO2 +2 H+ H H H C OH C O CH3 CH3 2 Acetaldehyde 2 Ethanol (a) Alcohol fermentation 2 ATP P i 2 ADP + 2 Glucose Glycolysis O– C O C O 2 NADH 2 NAD+ CH3 O 2 Pyruvate C O H OH C CH3 2 Lactate (b) Lactic acid fermentation Figure 9.17 Fermentation
Chapter 9: Cellular Respiration: Harvesting Chemical Energy • Why is respiration important? • What are redox rxns? • What are the 3 main steps of respiration? • What happens during glycolysis? • How is the ATP made? • How do electrons get from glucose to O2? • How does pyruvate get into the mitochondria for the Krebs Cycle? • What happens during the Citric Acid Cycle? • How many ATP so far? • How many electron carriers so far? • What happens during electron transport? • Why do electrons NEED to “break the fall?” • How is ATP made during chemiosmosis? • What happens when there is no O2? • How do the other foods we eat get catabolized?
Carbohydrates Proteins Fats Amino acids Fatty acids Sugars Glycerol Glycolysis Glucose Glyceraldehyde-3- P NH3 Pyruvate Acetyl CoA Citric acid cycle Oxidative phosphorylation Figure 9.19 The catabolism of various molecules from food
Chapter 9: Cellular Respiration: Harvesting Chemical Energy • Why is respiration important? • What are redox rxns? • What are the 3 main steps of respiration? • What happens during glycolysis? • How is the ATP made? • How do electrons get from glucose to O2? • How does pyruvate get into the mitochondria for the Krebs Cycle? • What happens during the Citric Acid Cycle? • How many ATP so far? • How many electron carriers so far? • What happens during electron transport? • Why do electrons NEED to “break the fall?” • How is ATP made during chemiosmosis? • What happens when there is no O2? • How do the other foods we eat get catabolized? • How is cellular respiration controlled?
Glucose AMP Glycolysis Stimulates Fructose-6-phosphate + Phosphofructokinase – – Fructose-1,6-bisphosphate Inhibits Inhibits Pyruvate Citrate ATP Acetyl CoA Citric acid cycle Oxidative phosphorylation Figure 9.20 The control of cellular respiration