2. Regents Biology Cellular Respiration Harvesting Chemical Energy ATP

3. Regents Biology Energy flow  Energy enters an ecosystem as sunlight  Photosynthesis converts this light energy into chemical energy, stored in organic compounds  Cellular respiration is the release of energy, in the form of ATP, from organic compounds in cells in the presence of oxygen

4. Regents Biology Energy needs of life  Animals are energy consumers  What do we need energy for?  To make new compounds for body  reproduction  active transport  movement  temperature control

5. Regents Biology Where do we get energy?  Energy is stored in organic molecules  carbohydrates, fats, proteins (in the bonds)  Animals eat these organic molecules  food  digest (break apart) food to get  fuels for energy (ATP)  raw materials for building more molecules  carbohydrates, fats, proteins, nucleic acids

6. Regents Biology ATP What is energy in biology?

7. Regents Biology What we all need to function: Money and Energy Change - - - - - - - - - - - - - - - - -ATP Large bills - - - - - - - - - - - Simple Sugars Checking - - - - - - - - - - - - Disaccharides Savings - - - - - - - - - - - - - -Starch, Lipids stocks, investments- - - - - -- Lipids, Proteins

8. Regents Biology Harvesting energy stored in food  Cellular respiration  breaking down food to produce ATP  happens in mitochondria  requires oxygen glucose + oxygen  carbon + water + energy dioxide C 6 H 12 O 6 6O 2 6CO 2 6H 2 OATP  + +++ heat

9. Regents Biology What do we need to make energy?  The “Furnace”  mitochondria  Fuel  food  carbohydrates, fats, proteins  The Helpers  oxygen  “aerobic”  enzymes O2O2 food ATP

10. Regents Biology “Burn fuels” to make energy CO 2 + H 2 O + heat fuel (carbohydrates) combustion making heat energy by burning fuels in one step ATP CO 2 + H 2 O + ATP (+ heat) respiration making ATP energy (& some heat) by burning fuels in many small steps in the presence of oxygen food (carbohydrates) O2O2 O2O2

11. Regents Biology Stepwise energy harvest  If energy is released from a fuel all at once, it cannot be harnessed efficiently for constructive work  For example, if a gasoline tank explodes, it cannot drive a car very far.

12. Regents Biology Efficiency:  We can only use about 40% of the energy contained in the food we eat  Remaining 60% of energy in glucose is lost as heat  Very efficient: most cars use only 25% of energy in gasoline  WOW!!!

13. Regents Biology

14. Using ATP to do work? A working muscle recycles over 10 million ATPs per second Can’t store ATP  too unstable  only used in cell that produces it  only short term energy storage  carbohydrates & fats are long term energy storage ATP ADP + P work

15. Regents Biology A Body’s Energy Budget food intake synthesis resting energy activity temperature control growth reproduction { { storage glycogen fat { ATP Potential energy Kinetic energy

16. Regents Biology Now how do we actually break apart this “glucose”?  We break the 6-carbon glucose in half in a process called Glycolysis  Then if oxygen is: absent present (anaerobic respiration) (aerobic respiration) It starts to ferment it goes to the kreb’s cycle Or produce lactic acid and finishes popping off carbons to get energy

17. Regents Biology LE 9-6_1 Glycolysis Pyruvate Glucose Cytoplasm ATP Mitochondria If oxygen IS present then …………

18. Regents Biology LE 9-6_2 Mitochondria Glycolysis Pyruvate Glucose ATP Kreb’s cycle Cytoplasm

19. Regents Biology Glycolysis Pyruvate Glucose ATP Kreb’s cycle ATP Electron Transport Chain ETC Electrons carried via NADH Electrons carried via NADH Mitochondria Cytoplasm

20. Regents Biology What if something is missing?  Can’t complete aerobic respiration  fermentation  bacteria & yeast  glucose  ATP + alcohol  beer, wine, bread, yogurt  anaerobic respiration  Animals and some bacteria  glucose  ATP + lactic acid  muscle fatigue

21. Regents Biology Any Questions??