5 Thylakoid membrane contains chloroplastH+ATPChloroplastsdouble membranestromafluid-filled interiorthylakoid sacsgrana stacksThylakoid membrane containschlorophyll moleculeselectron transport chainATP synthaseH+ gradient built up within thylakoid sacthylakoidouter membraneinner membranegranumstromathylakoidA typical mesophyll cell has chloroplasts, each about 2-4 microns by 4-7 microns long.Each chloroplast has two membranes around a central aqueous space, the stroma.In the stroma are membranous sacs, the thylakoids.These have an internal aqueous space, the thylakoid lumen or thylakoid space.Thylakoids may be stacked into columns called grana.
7 Pigments Pigments: molecules that absorb visible light Each pigment has a characteristic absorption spectrum, the range it is capable of absorbing.--chlorophyll a – primary pigment--chlorophyll b – secondary pigment-- carotenoids – accessory pigments
9 Two stages of photosynthesis: Light-dependent reactionsRequires light as a source of energyStep 1: chlorophyll uses energy from sun to split water moleculesStep 2: water molecules split into H & OStep 3: O2 released to atmosphereStep 4: chlorophyll stores some light energy in ATP
10 Photo phosphoryl ation Using lightAdding a phospate groupLight energy is used to add a high-energy phosphate group to a carrier molecule.A process
11 Light Reactions produces ATP produces NADPH H2OATPO2lightenergy+NADPHH2Osunlightproduces ATPproduces NADPHreleases O2 as a waste productEnergy BuildingReactionsNADPHATPO2
14 Light-Independent reactions (Calvin Cycle) Part of photosynthesis that doesn’t require lightStep 1: hydrogen which split from H2O combines with CO2 using energy stored in ATPStep 2: this combination forms glucose (C6H12O6)Step 3: water is formed (byproduct)
15 Making SugarThe energy captured in the Lt-Dep is now used to fix CO2 and make sugar.Stage 1. Fix CO2 to RuBP.Stage 2. Generater PGAL then sugar.Stage 3. Regenerate RuBP.
16 Calvin Cycle builds sugars uses ATP & NADPH recycles ADP & NADP CO2 C6H12O6+NADPATPNADPHADPCO2builds sugarsuses ATP & NADPHrecycles ADP & NADPback to make more ATP & NADPHADPNADPSugar BuildingReactionsNADPHATPsugars
17 Putting it all together CO2H2OC6H12O6O2lightenergy+H2OCO2Plants make both:energyATP & NADPHsugarssunlightADPNADPEnergy BuildingReactionsSugar BuildingReactionsNADPHATPO2sugars
21 Energy cycle ATP Photosynthesis Cellular Respiration sun CO2 O2 H2O even though this equation is a bit of a lie… it makes abetter storysunPhotosynthesisCO2H2OC6H12O6O2lightenergy+H2OplantsCO2glucoseO2animals, plantsCO2H2OC6H12O6O2ATPenergy+Cellular RespirationATPThe Great Circle of Life,Mufasa!