Stage IPrep stage before Stage IIStage IIStage IIIReview of Photosynthesis and Aerobic RespirationPhotosynthesis-occurs in plants, algae, cyanobacteria, endergonic reactionsProcess that takes sunlight energy to convert CO2 and H2O into glucose and O26CO2 + 12H2O -> glucose (C6H12O6) + 6O2 + 6H2O2 sets of reactions take place: Light Dependent and the Light IndependentLight Dependent reactions- occur in thylakoid membrane of chloroplast*Water is the reactant, O2, ATP and NADPH are the products*Photosystems have Chlorophyll A and accessory pigments which lose e- to a higher energy state when sunlight energy hits them and is absorbed*e-‘s move from photosystem II->ETS->photosystem I->ETS->NADPH (final acceptor)* Because e- are not returned to the original Ch. A, this movement of e- and the formation of ATP is called noncyclic photophosphorylation (formation of ATP, NADPH)*As e- move, they attract H+ ions into thylakoid compartment, creating a gradient*Photolysis is occurring during PS II, and results in O2, H+ ions, and electrons being released into thylakoid, helps create a H+ gradient along with e- attracting H+ ions through ETS*It is this H+ gradient, created by photolysis and ETS, which drives the formation of ATPby ATP synthase-this is called chemiosmosisLight Independent Reactions-occur in the stroma of chloroplast*CO2, ATP, NADPH are the reactants, glucose and water are the products*Carbon fixing is done through the Calvin Benson cycle*CO2 is attached to RuBP by the enzyme Rubisco*RuBP->PGA->PGAL->glucose->starch, cellulose, sucrose*it takes 2 PGAL to make 1 glucoseCombining both light dependent and light independent reactions: Sunlight energy ->photosystem II (excites e- in Ch. A)-> H2O ->photolysis-> O2 made-> ETS->photosystem I->ETS->NADPH, ATP made-> CO2->Calvin Benson cycle->glucoseAerobic Respiration-process which results in the breakdown of glucose in the presence ofoxygen to carbon dioxide and water to yield a large amount of ATP, exergonic reaction, all eukaryotic cellsglucose (C6H12O6) + 6O2-> 6CO2 + 6H2O + 36 (38) ATP3 stages:Stage I*glycolysis-breakdown of glucose to 2 pyruvate occurs in the cytoplasm*makes 2 NADH, 2 ATP net by substrate level phosphorylationPrep stage before Stage II*Pyruvate to Acetyl CoA occurs in mitochondria*Releases CO2, yields 2 NADHStage II*Kreb’s cycle occurs in mitochondria*Acetyl CoA combines with oxaloacetate to form citrate*releases 4 CO2*6 NADH, 2 FADH2, 2 ATP made by substrate level phosphorylationStage III*Electron Transport Phosphorylation (ETP)* NADH, FADH2 donate e- and H+ to ETP*O2 is the final electron acceptor, combines with excess H+ ions to form H2O*e- and H+ ions are moved through transport systems, creating a H+ gradient as was done in photosynthesis. Allows the formation of ATP by ATP synthase. This is chemiosmosis (just like in photosynthesis)*NADH makes3 ATP, FADH2 makes 2 ATP*Final ATP yield from ETP will be 34 ATP, Sequence of events during Aerobic Respirationglycolysis-->pyruvate->Acetyl CoA->Kreb’s Cycle->ETP->ATP made*Total ATP yield from all 3 stages of aerobic respiration will be 36 ATP from the complete breakdown of 1 glucose
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