Cell Reactions and Energy ATP: energy molecule of the cell bond holding the 3rd phosphate is a high energy bond and can be easily broken H 2 O + ATP -->

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  • Cell Reactions and EnergyATP: energy molecule of the cell

    bond holding the 3rd phosphate is a high energy bond and can be easily broken

    H2O + ATP --> ADP + Pi + Energy

  • Endergonic Reactions (energy IN), anabolic reaction (making molecules)Cell Reactions and EnergyExergonic Reactions (energy OUT),catabolic reactions (breaking molecules apart)

  • An anabolic processPhotosynthesisautotrophs produce their own food by photosynthesis;the process occurs in the chloroplast

  • Photosynthesisglucose + oxygenoverall reaction:carbon dioxide + water

  • Photosynthesisphotosynthesis occurs in two steps:

    1. Light Dependent Reactions:

    Making high energy productsLight Independent Reactions (carbon fixation):

    Using the high energy products to capture CO2

  • only take place in the presence of light1. Light dependent reaction solar energy is absorbed by chlorophyll in chloroplasts water molecules are split (oxygen is released into atmosphere, hydrogen takes part in light independent reactions) occurs in the thylakoid disk membrane

  • FORMULA:1. Light dependent reactionH20 + ADP +Pi + NADP+ 02 + ATP + NADPH [high energy products]

  • hydrogen and carbon dioxide combine to form glucose molecules2. Light independent reactionoccurs in the stromaplants use some glucose for life processes(e.g. growth, reproduction)most plants convert glucose to starch (for storage)

  • FORMULA:2. Light independent reactionCO2 + ATP + NADPHC6H12O6 + ADP+Pi + NADP+

  • Photosynthesissolar energy + CO2 + H2O C6H1206 + O2overall reaction:

  • Cell Respirationcell respiration is the release of energy from food (glucose)all cells perform this catabolic processcell respiration occurs in two steps:

    Step 1: Glycolysis

    Step 2: Aerobic or Anaerobic respiration

  • occurs in the cytoplasm

    1. GlycolysisFORMULA:glucose + 2 ADP + 2 Pi + 2 NAD+ 2 pyruvate + 2 ATP + 2 NADH

  • this process does not produce very much energy1. Glycolysismost of the energy is still contained in the bonds of the 2 pyruvatesthere are three possible reactions that break down pyruvate (step 2)

  • Step 2: getting rid of pyruvateCell Respirationcells must replace NAD+ as it is needed in glycolysis and if the cell runs out, glycolysis stops


  • 2a. Aerobic Cellular Respiration

    occurs in the mitochondriathe process is aerobic (oxygen dependent)2 pyruvate + O2 H2O + CO2 + 34 ATP

  • 2b. Anaerobic cellular respirationLactic Acid Fermentation:

    occurs only in animal muscle cells that are deprived of oxygenif oxygen is unavailable for aerobic respiration, the cell converts the pyruvate into lactic acid which causes muscle crampswhen oxygen is available, the lactic acid is converted back into pyruvate

  • 2b. Anaerobic cellular respirationLactic Acid Fermentation:

    FORMULA:pyruvate + NADHlactic acid + NAD+

  • 2b. Anaerobic cellular respirationAlcohol Fermentation:occurs in anaerobic yeast and bacteria,as they do not have mitochondriaFormula:2 pyruvate + 2 NADH 2 NAD+ + 2 ethanol + 2CO2 process is used to make alcoholic beverages

  • LACTIC ACID ALCOHOL FERMENTATION FERMENTATIONCOMPARISON ANAEROBICGlycolysis2 ATP Glycolysis2 ATPProduct: lactic acid Product:ethanol + CO2Potential:34 more ATP Potential:no more ATP


    Glycolysis 2 ATP Glycolysis2 ATPStep 2:34 ATP Step 2:0 ATP36 ATP2 ATP

    Photosynthesis Flow Chart


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