1 / 51

UNIT 2 Lecture 6

UNIT 2 Lecture 6. Metabolism. Unit 2: Life’s Energy Sources and Conversions. Metabolism Cellular Respiration: Sugar  ATP Photosynthesis: Light  Sugar. Key Themes. • Energy acquisition & conversions in metabolism. The Molecules of Life Structure-Function Relationship

skylar
Download Presentation

UNIT 2 Lecture 6

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. UNIT 2Lecture 6 Metabolism

  2. Unit 2: Life’s Energy Sources and Conversions • Metabolism • Cellular Respiration: Sugar  ATP • Photosynthesis: Light  Sugar

  3. Key Themes • Energy acquisition & conversions in metabolism The Molecules of Life Structure-Function Relationship Life’s Energy Conversions

  4. Metabolism An organism’s metabolism is the total of the organism’s chemical reactions • Two types of reactions: • Big molecule Several small molecules • Releases energy • Small molecules Big molecule • Requires energy

  5. Metabolism An organism’s metabolism is total of the organism’s chemical reactions • Two types of reactions: • Big molecule Several small molecules • Releases energy • This sounds like: • Cellular respiration • Photosynthesis • Neither

  6. Order and Chaos Energy Nature “wants” to be random/chaotic Energy Mydesigningsolutions.com; bedroomdisaster.blogspot.com; fritolay.com; slashfood.com

  7. Order and Chaos A complex, ordered molecule Several small, disordered molecules Energy Nature “wants” to be random/chaotic Several small, disordered molecules A complex, ordered molecule Energy Mydesigningsolutions.com; bedroomdisaster.blogspot.com; fritolay.com; slashfood.com

  8. CO2 H2O Glucose Requires Energy Releases Newenergyandfuel.com; ualberta.ca; all-water.org

  9. Fig. 8-6 Reactants Amount of energy released Energy Energy Products Progress of the reaction (a) Energy-releasing reactions Products Amount of energy required Energy Energy Reactants Progress of the reaction (b) Energy-requiring reactions

  10. Fig. 9.2 Ecosystem energy flow Light energy 1. Be able to link producers and consumers via cycles of energy and carbon flow ECOSYSTEM ATP Photosynthesis in chloroplasts Organic molecules CO2 + H2O + O2 Cellular respiration in mitochondria ATP ATP then powers cellular work Heat energy

  11. Light energy 1. Be able to link producers and consumers via cycles of energy and carbon flow ECOSYSTEM ATP Photosynthesis in chloroplasts Organic molecules CO2 + H2O + O2 Cellular respiration in mitochondria ATP ATP then powers cellular work Fig. 9.2 Energy flow in ecosystems Heat energy

  12. Light energy ECOSYSTEM ATP Photosynthesis in chloroplasts Organic molecules CO2 + H2O + O2 Cellular respiration in mitochondria ATP ATP then powers cellular work Fig. 9.2 Energy flow in ecosystems Heat energy

  13. Chaos = Entropy CO2 H2O Glucose Requires Energy Releases Low Entropy System (less random, more ordered) High Entropy System (more random, less ordered) Newenergyandfuel.com; ualberta.ca; all-water.org

  14. CO2 H2O Glucose Requires Energy Releases Potential energy is stored in chemical bonds (C-H especially) Newenergyandfuel.com; ualberta.ca; all-water.org

  15. Heat CO2 + Chemical energy H2O Cells’ ability to store energy in chemical bonds is what makes organisms and ecosystems function

  16. There is no way to convert light energy into chemical energy Heat CO2 + Chemical energy H2O Cells’ ability to store energy in chemical bonds is what makes organisms and ecosystems function Without photosynthesis…

  17. Heat CO2 + Chemical energy H2O What about cellular respiration? Without cellular respiration: • Nothing could live • No animals could live • Nothing non-photosynthetic could live • Everything could live

  18. Where does energy go?

  19. Where does energy go in an ecosystem? • Heat, growth, reproduction, etc. Heat Heat Heat Heat

  20. Trophic levels: Energy Flow Through Ecosystem http://www.britannica.com/EBchecked/media/15/Transfer-of-energy-through-an-ecosystem

  21. 5 minute break

  22. Energy for all cellular work is provided by the same energy-rich compound: ATP (adenosine triphosphate) A cell (in any organism) constantly performs work that requires energy:

  23. Fig. 8.8 ATP ATP consists of three phosphate groups, a sugar, and a nitrogenous base. What does that sound like? A) a triglyceride B) a nucleotide C) a phospholipid D) a trisaccharide

  24. Nitrogenous base Phosphate group Sugar (b) Nucleotide Fig. 5.27 Each nucleotide is composed of: a monosaccharide sugar, a phosphategroup, and a (N-containing) nitrogenous base A = adenine A + Ribose = adenosine adenosine mono-phosphate (AMP) adenosine di-phosphate (ADP) adenosine tri-phosphate (ATP) Fig. 8.8

  25. ATP + H2O Energy loaded onto ATP Energy released from ATP Energy from breakdown of energy-rich molecules Energy for cellular work ADP + P i ATP takes the energy released from the breakdown of energy-rich food molecules and does cellular work Fig. 8.12

  26. Fig. 8-9 P P P Adenosine triphosphate (ATP) H2O + P P P Energy + i Inorganic phosphate Adenosine diphosphate (ADP)

  27. ATP: Energy carrier Higher Energy Fig. 8.8 “Phosphorylated” (=energized!) molecule Lower Energy +

  28. High-energy P transferred to motor proteins for mechanicalwork ADP + ATP P i Vesicle Cytoskeletal track ATP Protein moved Motor protein ATP transfers phosphate groupto motor protein (phosphorylatedmotor protein = energized) Fig. 8.11 (b) See Campbell Figures 50.27 & 50.29 for additional details on muscle contraction.

  29. Membrane protein (Na+/K+ pump) P P i Na+ moved uphill Na+ ADP + ATP P i High-energy P transferred to transport proteins for transportwork Fig. 8.11 (a); see also Fig. 7.16 for more detail

  30. Na+/K+ Pump • Cells want to pump Na+ out • Cells want to pump K+ in Na+ K+ ATP

  31. 8. Be able to apply the principal features and functions of an ATP-fueled ion pump to the Na+/K+ pump Active transport and the sodium-potassium pump Both Na+ and K+ are moved AGAINST their concentration gradient See Fig. 7.16 for a six panel, blow-by-blow description of the sodium-potassium pump. http://www.colorado.edu/ebio/genbio/07_16ActiveTransport_A.html

  32. http://onlinephys.com/circuit1.html

  33. Fig.8.7 http://onlinephys.com/circuit1.html

  34. Cotransport: Using potential energy Na+ ATP fuels the Na+/K+ pump Na+ accumulates “on top of the hill” (against its concentration gradient) Na+ flows downhill again Releasing useful energy ATP

  35. Cotransport: Using potential energy Na+ ATP fuels the Na+/K+ pump Na+ accumulates “on top of the hill” (against its concentration gradient) POTENTIAL ENERGY Na+ flows downhill again Releasing useful energy ATP 35

  36. Cotransport: Using potential energy This potential energy can be used… To transport other molecules AGAINST their concentration gradient

  37. The Na+ gradient built up by the Na+/K+ pump also fuels the secondary active transport of glucose (& other substances) AGAINST their concentration gradient In Na+/glucose co-transport, Na+ flows back downhill & dragsglucose uphill AGAINST its concentration gradient

  38. What provides the energy for the uphill transport of Na+ against its concentration gradient? • No energy is needed. • the Na+/K+ transport protein itself • ADP and Pi • ATP

  39. What provides the energy for the Na+/glucose cotransporter? • No energy is needed. • the Na+ gradient • ATP as a direct energy source • ATP as an indirect energy source • B and D

  40. Membrane protein (Na+/K+ pump) P P i Na+ moved uphill Na+ ADP + ATP P i High-energy P transferred to transport proteins for transportwork Fig. 8.11 (a); see also Fig. 7.16 for more detail 41

  41. P (ATP adds phosphate group to glutamic acid, making it less stable.) ADP + + ATP Glu Glu NH2 P (Ammonia displaces phosphate group, forming the amino acid glutamine.) NH3 P + + i Glu Glu High-energy P transferred to reactant molecules for chemicalwork Fig. 8.10 (b)

  42. Energy for all 3 types of work provided by: ATP (adenosine triphosphate) Summary: To stay alive, living cell performs 3 kinds of work that require energy: 1. Mechanicalwork 2. Transportwork 3. Chemical work

  43. • ATP is too unstable to serve as an actual storageform of energy. • Therefore, C-H bonds in macromolecules(e.g. sugars) are instead used for energy storage.

  44. CO2 + H20 Sugar [CH2O]x + O2 Since ATP is too unstable, C-H bonds in sugars are used for energy storage. Converts solar energy to ATP and uses ATP to make sugars Photosynthesis: Light (energy) ATP ATP Respiration: Converts the energy of sugars back to ATPas needed.

  45. Hank’s crash course in ATP 0-3:30 http://www.youtube.com/watch?v=00jbG_cfGuQ&feature=relmfu

  46. Key Themes (2) “Think Like a Biologist”: Understand What Life Is. “Unity” of life: What are common features of eukaryotes? Energy conversions: Sugar breakdown & mitochondrial ATP formation

  47. Fig. 9.1 Respiration Food-to-Energy Fig. 8.3

  48. Light energy ECOSYSTEM Photosynthesis in chloroplasts Organic molecules CO2 + H2O + O2 Cellular respiration in mitochondria ATP ATP powers most cellular work Heat energy Cellular respiration breaks down energy-rich molecules to CO2 & water, extracting their energy. Low energy High energy C-H bond! “burned” with O2 to form H2O + CO2 Fig. 9.2

  49. CO2 + H20 Sugar [CH2O]x + O2 Since ATP is too unstable, C-H bonds in sugars are used for energy storage. Converts solar energy to ATP and uses ATP to make sugars Photosynthesis: Light (energy) ATP ATP Respiration: Converts the energy of sugars back to ATPas needed.

More Related