1 / 28

Energy and Life

Energy and Life. Living things need energy to survive comes from food energy in most food comes from the sun Plants use light energy from the sun to produce food autotrophs organisms that make their own food Ex - plants

lopezjames
Télécharger la présentation

Energy and Life

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. Energy and Life • Living things need energy to survive • comes from food • energy in most food comes from the sun • Plants use light energy from the sun to produce food • autotrophs organisms that make their own food • Ex - plants • heterotrophs organisms that must obtain energy from the foods they consume • animals

  2. 9-1 Chemical Pathways • Food serves as a source of raw materials for the cells in the body and as a source of energy. Animal Cells Animal Mitochondrion Plant Plant Cells

  3. Chemical Energy and ATP • Energy – the ability to do work • Forms: light, heat, electricity, chemical compounds • chemical compound that cells use to store and release energy is adenosine triphosphate (ATP) • ATP - basic energy source for all cells

  4. Chemical Energy and ATP • ATP consists of: • adenine • ribose (a 5-carbon sugar) • 3 phosphate groups The three phosphate groups are the key to ATP's ability to store and release energy. Adenine Ribose 3 Phosphate groups ATP

  5. Chemical Energy and ATP • Storing Energy • ADP has two phosphate groups instead of three. • A cell can store small amounts of energy by adding a phosphate group to ADP. ATP ADP + Energy Adenosine Triphosphate (ATP) Adenosine Diphosphate (ADP) + Phosphate Fullycharged battery Partiallycharged battery

  6. Chemical Energy and ATP • Releasing Energy • Energy stored in ATP is released by breaking the chemical bond between the second and third phosphates. 2 Phosphate groups P ADP

  7. Chemical Energy and ATP ATP energy uses: • cellular activities: active transport, protein synthesis • muscle contraction • Most cells have only a small amount of ATP, because it is not a good way to store large amounts of energy. • Cells can regenerate ATP from ADP as needed by using the energy in foods like glucose.

  8. Cellular Respiration • So what do our cells do with the Oxygen and why do they give off Carbon Dioxide? • Answer: To make ATP!

  9. Cellular Respiration C6H12O6 + 6O2 6CO2 + 6H2O + usable energy (ATP)

  10. Cellular Respiration (3-stages) • Glycolysis • Krebs Cycle (Citric Acid Cycle) • Electron Transport Chain (ETC)

  11. Overview of Cellular Respiration • If oxygen is present: • cellular respiration - the process that releases energy by breaking down glucose and other food molecules in the presence of oxygen • glycolysis  Krebs cycle  electron transport chain • equation: • 6O2 + C6H12O6 → 6CO2 + 6H2O + Energy • oxygen + glucose → carbon dioxide + water + Energy

  12. Flowchart Section 9-2 Cellular Respiration Carbon Dioxide (CO2) + Water (H2O) + ATP Glucose(C6H1206) + Oxygen(02) Glycolysis KrebsCycle ElectronTransportChain

  13. Figure 9–3 Glycolysis Glycolysis: Step 1 Glucose 2 Pyruvic acid To the electron transport chain

  14. Figure 9–3 Glycolysis Section 9-1 Glucose 2 Pyruvic acid To the electron transport chain

  15. Figure 9–3 Glycolysis Section 9-1 Glucose 2 Pyruvic acid To the electron transport chain

  16. Where Cytoplasm • NO O2 required • Energy Yield net gain of 2 ATP at the expense of 2 ATP • 6-C glucose  TWO 3-C pyruvates • Free e- and H+ combine with organic ion carriers called NAD+ NADH + H+ (nicotinamide dinucleotide)

  17. Summary • In Glucose (6-C) 2 ATP • Out 2 pyruvate; 2(3-C) 2NADH a net of 2 ATP

  18. Breakdown of Pyruvic Acid • Where mitochondria • Pyruvate (3-C)  Acetic acid (2-C) • 3rd C forms CO2 • Acetic acid combines with Coenzyme A to form ACETYL-CoA

  19. The Krebs Cycle Section 9-2 Citric Acid Production Mitochondrion

  20. Krebs Cycle

  21. Second Step: Citric Acid Cycle (Krebs Cycle) • Where Mitochondrial matrix • Energy Yield 2 ATP and more e- • Acetyl-CoA (2-C) combines with 4-C to form 6-C CITRIC ACID • Citric Acid (6-C) changed to 5-C then to a 4-C • Gives off a CO2 molecule • NAD+ and FAD pick up the released e- • FAD becomes FADH2 • NAD+ becomes NADH + H+ • Cycle ALWAYS reforming a 4-C molecule

  22. ETC • Where inner membrane of mitochondria • Energy Yield Total of 32 ATP • O2 combines with TWO H+ to form H2O • Exhale - CO2, H2O comes from cellular respiration

  23.  Electron Transport Chain Section 9-2 Electron Transport Hydrogen Ion Movement Channel Mitochondrion Intermembrane Space ATP synthase Inner Membrane Matrix ATP Production

  24. Mitochondrion Electrons carried in NADH Electrons carried in NADH and FADH2 Pyruvic acid Glucose Electron Transport Chain Krebs Cycle Glycolysis Mitochondrion Cytoplasm Summary

  25. Aerobic vs. Anaerobic • Anaerobic DOES NOT require oxygen • Fast, but produces smaller amounts of energy (ATP) • Aerobic requires oxygen • Yields large amounts of energy

More Related