Cellular Respiration Harvesting Chemical Energy

1. Cellular RespirationHarvesting Chemical Energy ATP

2. fuel(carbohydrates) CO2 + H2O + heat O2 “Burning fuels” to make energy combustion making heat energy by burning fuels in one step

3. ATP O2 food(carbohydrates) “Burning fuels” to make energy Aerobic respiration making ATP energy (& some heat) by burning fuels in many small steps ATP +CO2 + H2O (+ heat)

4. Energy needs of life • Animals are energy consumers • Why do we need energy? • synthesis(building for growth) • reproduction • active transport • movement • temperature control (heat)

5. Where do we get energy? • Energy is stored in organic molecules • carbohydrates, fats, proteins • Animals eat organic molecules  food • digest food to get • fuels for energy • raw materials for building more molecules • carbohydrates, fats, proteins, nucleic acids ATP

6. What is energy in biology? ATP Adenosine TriPhosphate Whoa!HOT stuff!

7. ATP ATP + 6CO2 + 6H2O  C6H12O6 + 6O2 food glucose+oxygenenergy+carbon+ water dioxide O2 Harvesting energy stored in food • Cellular respiration • breaking down food to produce ATP • in mitochondria • using oxygen • “aerobic” respiration • usually digesting glucose • but could be other sugars, fats, or proteins

8. food O2 ATP CO2 H2O What do we need to make energy? Make ATP!Make ATP!All I do all day…And no oneeven notices! • The “Furnace” for making energy • mitochondria • Fuel • food:carbohydrates, fats, proteins • Helpers • oxygen • enzymes • Product • ATP • Waste products • carbon dioxide • then used by plants • water enzymes

9. Mitochondria are everywhere!! animal cells plant cells

10. Using ATP to do work? • Can’t store ATP • toounstable • used only in the cell that produces it • short term energy storage • carbohydrates & fats are long term energy storage ATP Adenosine TriPhosphate work Whoa!Pass me theglucose & oxygen! Adenosine DiPhosphate ADP A working muscle recycles over 10 million ATPs per second

11. How organisms turn fuel into ATP Fuel (carbohydrates, lipids, proteins) Oxygen present? no yes Anaerobic Cellular Respiration Aerobic Cellular Respiration ATP Alcoholic Fermentation Lactic Acid Fermentation ATP ATP ATP ATP ATP Makes only a little ATP Makes a LOT of ATP

12. Aerobic Cellular Respiration 3 Major Steps: • Glycolysis • Krebs Cycle • Electron Transport Chain

13. 1. Glycolysis • Glyco= glucose lysis= splitting • Where: in the cytoplasm • Uses:NOoxygen • Makes: • Pyruvate (passed to Krebs Cycle) • A little ATP • NADH(electron bus… headed to the Electron Transport Chain)

14. Glycolosis (no O2 required) Glucose  G3P  2 Pyruvate

15. 2. Krebs Cycle • Where? • in the mitochondrial matrix • Uses: - pyruvate (from glycolysis) • Makes: • NADH (electron bus) • FADH2 (electron bus) • A littleATP (energy) • Carbon Dioxide (waste product)

16. Krebs Cycle • 2 Acetyl CoA enters cycle to form Citric Acid one at a time

17. 3. Electron Transport • Where? • Inner mitochondrial membrane • Uses: • NADH & FADH2 • Remember these are like “electron buses” that drop off electrons to the ETC (aka: electron transport chain) • Oxygen • Pulls electrons down the ETC and accepts them at the end of the ETC • This is why we die if we don’t get oxygen! • Makes: • Water(waste product) • A BUNCH of ATP • (whoohooo… big energy!) ATP Important!

18. How does the ETC make so much energy (ATP)? Electron Transport Answer =Chemiosmosis Sound familiar? We learned it in photosynthesis too!

19. Electron Transport • NADH & FADH2drop off electrons • Electrons move down the electron transport chain • pulled down the chain by oxygen • Hydrogen ions diffuse from an area of high concentration (outside the membrane) to an area of low concentration (inner-membrane space) through ATP synthase. • ATP synthase is like an energy turbine, producing lots of ATP!

20. Electron Transport

21. O2 Anaerobic Respiration We know that aerobic cellular respiration requires oxygen, but what happens if there is no oxygen available? Answer = Anaerobic Cellular Respiration

22. O2 Anaerobic Respiration • The anaerobic pathway that follows glycolysis • If there is nooxygen present and an organism needs energy, the cell may use anaerobic respiration to continue producing ATP

23. O2 Anaerobic Respiration • also known as fermentation • alcohol fermentation • lactic acid fermentation • no oxygen • no mitochondria (bacteria) • makes very little ATP • large animals cannot survive yeast bacteria

24. O2 Anaerobic Respiration • Fermentation • alcohol fermentation • yeast • glucose  ATP + CO2+ alcohol • make beer, wine, bread • lactic acid fermentation • bacteria, animals • glucose  ATP + lactic acid • bacteria make yogurt • animals feel muscle fatigue Tastes good…but not enoughenergy for me!

25. Questions! Number your paper 1 to 4

26. What is the overall purpose of cellular respiration? • to make ATP • to produce H2O • to store glucose • to deliver oxygen

27. TCA cycle chemiosmosis glycolysis glycolysis Krebs cycle electron transport electron absorption catalysis phosphorylation aerobic pathway anaerobic pathway fermentation Which represents the general sequence of cellular respiration?

28. Which stage of cellular respiration is the anaerobic process? • glycolysis • Krebs cycle • electron transport

29. Which molecule generated by the Krebs Cycle is a waste product? • CoA • CO2 • FADH2 • NADH

30. Answers • A • B • A • B

31. Video