ATP is the energy storing molecule in cells. [1] It releases energy quickly whenever a cell needs it. [2] Photosynthesis uses sunlight to produce ATP, oxygen, and glucose from carbon dioxide and water. [3] It occurs in chloroplasts and has two stages - the light-dependent reaction produces ATP and NADPH, while the light-independent Calvin cycle uses these to produce glucose.

1. CHAPTER 9 ENERGY IN A CELL

2. ENERGY All living organisms must be able to obtain energy from their environment All energy comes from sunlight and organisms either obtain it directly or indirectly

3. ADENOSINE TRIPHOSPHATE ( ATP) Energy storing molecule. Releases energy quickly whenever a cell needs it.

4. ATP Structure Composed of an adenosine molecule with three phosphate molecules attached. The energy of ATP becomes available when the bond is broken between the 2 nd and 3 rd phosphate groups. adenosine TRI phosphate to adenosine DI phosphate

5. ATP

6. Photosynthesis The process that uses sunlight to make simple sugars. Contains 2 reactions.

7. Light - dependent reaction Requires light in order to occur. Reactants: Sunlight and water. Products: ATP and NADPH and releases oxygen.

8. Light - Independent Reaction Also known as the dark cycle or calvin cycle. Does not need sunlight in order to occur. Reactants: ATP, NADPH, and Carbon dioxide. Products: Glucose and Pgal.

9. Calvin Cycle OR Dark Cycle

10. Formula for photosynthesis 6CO 2 + 6H 2 O + sunlight -> C 6 H 12 O 6 + 6O 2

11. Chloroplast The plant organelle in which photosynthesis occurs. Contains pigments called chlorophyll that absorbs most wavelengths of light except green.

12. Chloroplast

13. Aerobic Cellular Respiration (with Oxygen) Breakdown of sugar (food) into ATP (usable energy). Occurs in the mitochondria. 3 phases: 1. glycolysis: Anaerobic (no oxygen) *Steps 2&3 with oxygen 2. citric acid cycle (kreb cycle) 3. electron transport chain

14. Mitochondria

15. Formula for aerobic respiration Opposite of photosynthesis. C 6 H 12 O 6 + O 2 -> 6CO 2 + 6H 2 O + energy

16. GLYCOLYSIS (sugar splitting) Anaerobic : no oxygen is used. Takes the 6-Carbon glucose and breaks it into 2, 3-Carbon pyruvic acid molecules.

17. Glycolysis Cont… Only produces 2 ATP molecules

18. Glycolysis Cont… Pyruvic acid is then converted into Acetyl Co-enzyme A before it enters the citric acid cycle. Reactants: Glucose Products: Pyruvic Acid

19. CITRIC ACID CYCLE (Also called the Kreb Cycle) During this process high energy electrons are captured by NADH and FADH 2 . (electron carriers) Pulls carbons off the sugar molecules, releasing carbon dioxide and generating 2 ATP (varies) . Reactants: Acetyl Co-enzyme A Products: NADH and FADH 2

20. Kreb Cycle ( Citric Acid Cycle)

21. ELECTRON TRANSPORT CHAIN The electron carriers NADH and FADH 2 transfer their electrons to the electron transport chain. The electrons are passed through a series of proteins, gradually releasing the energy they contain, to form 32 ATP molecules. The final electron acceptor is oxygen .

22. Electron Transport Chain

23. Aerobic Respiration

24. Anaerobic Respiration (No oxygen) Lactic acid fermentation: Occurs during strenuous exercise when the body is not able to supply needed oxygen to the muscles. Allows the continued production of ATP until oxygen levels are restored .

25. Anaerobic Respiration Cont... No Oxygen!!! Occurs in the cytoplasm of the cell. Produces lactic acid. Not very efficient – Only 2 ATP produced.

26. Anaerobic Respiration Cont.. Alcoholic Fermentation Used by yeast and some bacteria. Produces carbon dioxide and alcohol.