1 / 45

Releasing Chemical Energy (Ch. 8)

Respiration Rap……. Releasing Chemical Energy (Ch. 8). Giant panda snacking on bamboo. Aerobic Respiration Steps. 1) Glycolysis 2) Krebs Cycle 3) E.T.C. Step 1: Glycolysis. In cytoplasm (cytosol: not organelle) Start: glucose (6 C sugar), electron-empty NAD (NAD+), ADP, phosphate

lora
Download Presentation

Releasing Chemical Energy (Ch. 8)

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript

  1. Respiration Rap…… Releasing Chemical Energy (Ch. 8) • Giant panda snacking on bamboo

  2. Aerobic Respiration Steps • 1) Glycolysis 2) Krebs Cycle 3) E.T.C.

  3. Step 1: Glycolysis • In cytoplasm (cytosol: not organelle) • Start: glucose (6 C sugar), electron-empty NAD (NAD+), ADP, phosphate • End: 2 ATP, two 3-C molecules (pyruvic acid), two NADH.

  4. Where are we now? • Glycolysis done, now Krebs Cycle.

  5. O O Step 2: Krebs Cycle • Part 1: grooming pyruvic acid (3-C) • Start: pyruvic acid, Coenzyme A (CoA), NAD+ • End: Acetyl-CoA CO2 NADH pyruvate coenzyme A (CoA) NAD+ carbon dioxide NADH CoA acetyl-CoA

  6. =CoA acetyl-CoA CoA oxaloacetate citrate H2O NADH ATP NAD+ H2O O O O O isocitrate malate NAD+ H2O NADH fumarate FADH2 a-ketoglutarate FAD NAD+ CoA NADH succinate succinyl-CoA ADP + phosphate group Step 2: Krebs Cycle • Part 2: Actual Krebs Cycle • 2-C piece added to 4-C piece to start

  7. =CoA acetyl-CoA CoA oxaloacetate citrate H2O NADH ATP NAD+ H2O O O O O isocitrate malate NAD+ H2O NADH fumarate FADH2 a-ketoglutarate FAD NAD+ CoA NADH succinate succinyl-CoA ADP + phosphate group Step 2: Krebs Cycle • Same 4-C piece comes out at end • 2 CO2 represent the 2 Cs put in by Acetyl CoA.

  8. =CoA acetyl-CoA CoA oxaloacetate citrate H2O NADH ATP NAD+ H2O O O O O isocitrate malate NAD+ H2O NADH fumarate FADH2 a-ketoglutarate FAD NAD+ CoA NADH succinate succinyl-CoA ADP + phosphate group Step 2: Krebs Cycle • Part 2: 1 ATP made by direct phosphorylation • 3 NADH made.

  9. =CoA acetyl-CoA CoA oxaloacetate citrate H2O NADH ATP NAD+ H2O O O O O isocitrate malate NAD+ H2O NADH fumarate FADH2 a-ketoglutarate FAD NAD+ CoA NADH succinate succinyl-CoA ADP + phosphate group Step 2: Krebs Cycle • FAD shows up!(electron carrier) • Reduced: FADH2 • Holds high energy electrons from C.

  10. Step 2: Krebs Cycle • Summary: • Pyruvic acid enters: all 3 C oxidized to CO2 • Some ATP made (direct phosphorylation) • Lots high energy electron carriers made (NADH, FADH2).

  11. Where are we now? • Glycolysis and Krebs Cycle done, now: E.T.C. • Why? • Most glucose energy in reduced electron carriers (NADH & FADH2) • How make into ATP? E.T.C.

  12. Last Step: E.T.C. • Flashback!

  13. Last Step: E.T.C. • In mitochondrion. Inner & outer membranes

  14. Last Step: E.T.C. • 1) Electrons from electron carriers donated to E.T.C. • Electron carriers oxidized: NAD+ & FAD

  15. Last Step: E.T.C. • 2) Electrons move: lose energy, H+ crosses membrane

  16. Last Step: E.T.C. • 3) O accepts low energy electrons & H+ to make water • 4) ATP synthase: H+ cross membrane, release energy, ATP made

  17. Last Step: E.T.C. • The E.T.C. show……. Click here for the movie! The Song….. “Let’s start the show…..” Warning: contains graphic images of high energy electrons and overt scenes of oxidation and reduction. Parental discretion advised.

  18. Where are we now?

  19. What my students hear when I lecture.... A word about...Studying! Blah, blah, blah..... • Respiration Rap……

  20. Finishing Ch. 8 • Aerobic respiration done! • C in glucose oxidized • Low energy C (C-O bonds) • Some energy transferred ATP.

  21. Summary Equation for Aerobic Respiration C6H12O6 + 6O2 6CO2 + 6H2O glucose oxygen water carbon dioxide Finishing Ch. 8 • Flashback: Equation aerobic respiration.

  22. Finishing Ch. 8: Quick Summary • Glycolysis: glucose into 2 pyruvic acid, makes 2 ATP and 2 NADH • Krebs cycle: pyruvic acid C oxidized to CO2. Some ATP made: most energy in NADH and FADH2 • E.T.C.: NADH & FADH2 energy to ATP. O2 empties chain: combines electrons & H+ to form water.

  23. ATP accounting: how much? Glycolysis: 2 Krebs cycle: 2 E.T.C.: 32 About 36!

  24. Summary Equation for Aerobic Respiration C6H12O6 + 6O2 6CO2 + 6H2O glucose oxygen water carbon dioxide Focus on water • Water made (“metabolic water”) • Kangaroo rat!

  25. Making ATP when no O2 • Fermentation: Glycolysis plus 1 step • Step makes electron-empty NAD+ again • Not efficient: only 2 ATP per glucose!. • Alcoholic fermentation: yeast cells (fungi).

  26. Making ATP when there’s no O2 • Alcoholic fermentation (yeast cells: fungi). • Start: glucose, NAD+, ADP, phosphate • End: CO2 + ethanol (2C), NAD+, 2 ATP No O No mitochondrion

  27. Alcoholic fermentation summary • Rest energy? In ethanol C-H bonds (burns!)

  28. Making ATP when there’s no O2 • Human cells can do fermentation • Ex: muscles when O runs low • Alcoholic fermentation?

  29. Making ATP when there’s no O2 • Lactic acid fermentation: Glycolysis + extra step • Start: glucose, NAD+, ADP, phosphate • End: lactic acid (3C), NAD+, 2 ATP No O No mitochondrion

  30. Making ATP processes: summary • Aerobic respiration: glycolysis, Krebs cycle, ETC. Yields 36 ATP: needs O2!

  31. Making ATP processes: summary • Fermentation: glycolysis plus 1 step (alcoholic or lactic acid fermentation). Yields 2 ATP: works w/o O

  32. Making ATP from molecules other than glucose • Proteins, fats have energy (C-H bonds) • Your cells can convert those into ATP • How? • Link chemical pathways by common intermediates.

  33. 2 pathways:(letters stand for particular molecules) Pathway 1: A G I Q Pathway 2: X B G R G in both pathways: common intermediate

  34. Common intermediates can link pathways Cell can make R or Q, starting from A or X. Pathway 1: A X B R Pathway 2: G I Q

  35. Making ATP from molecules other than glucose • Common intermediates fed into aerobic respiration • Reverse: common intermediates build proteins, fats, or carbohydrates.

  36. How energy into C molecules? • Respiration generates ATP • Photosynthesis: puts energy into molecules • Converts light energy to chemical energy.

  37. Photosynthesis (Ch. 7) Anabaena (lab 3) • Photosynthetic organisms: producers or autotrophs • Put energy into life! Plants, algae, photosynthetic bacteria

  38. Photosynthesis (Ch. 7) • (Mostly) reverse aerobic respiration • Endergonic reaction • Oxidation & reduction: C reduced (H replaces O).

  39. Low energy wavelength High energy wavelength Setting stage: light & pigments • Photosynthesis captures light energy • What’s light? Electromagnetic radiation • Particle & wave (wavelength: distance peak to peak) • Long wave: little energy (vice versa)

  40. Setting the stage • Single unit light called “photon”.

  41. Wavelength of light (nanometers) Setting the stage: light and pigments • Visible light wavelengths: nanometers (nano: one billionth or 10-9 meters!).

  42. Setting the stage: light and pigments • Pigment: molecule absorbs light energy • “Absorb:” capture energy photon into electron energy

  43. Setting the stage: light and pigments • Plant pigments: • Chlorophyll (2 forms: “a” & “b”) • Accessory pigments (carotene & xanthophyll). chlorophyll a

  44. Setting the stage: light and pigments • Plant pigments: • Chlorophyll (2 forms: “a” & “b”) • Accessory pigments (carotene & xanthophyll). beta-carotene

  45. Setting the stage: light & pigments • Absorption of colors varies

More Related