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(c) Euglena. (d) Cyanobacteria. (b) Kelp. (a) Mosses, ferns, and flowering plants. Chapter 7 - Photosynthesis. Almost all plants are photosynthetic autotrophs, as are some bacteria and protists. They generate their own organic matter through photosynthesis.
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(c) Euglena (d) Cyanobacteria (b) Kelp (a) Mosses, ferns, and flowering plants Chapter 7 - Photosynthesis • Almost all plants are photosynthetic autotrophs, as are some bacteria and protists • They generate their own organic matter through photosynthesis..
Photosynthesis occurs in the chloroplasts, which: • Are found in the cells of the mesophyll • Contain stroma, a thick fluid • Contain thylakoids, membranous sacs in stacks called grana.. Vein Chloroplast Meso- phyll Inner membrane Outer membrane Stomata Leaf cross section Mesophyll cell Grana Stroma Thylakoid Thylakoid space
Light energy Photo-synthesis Oxygen gas Glucose Carbon dioxide Water The Overall Equation for Photosynthesis • The reactants and products of the reaction..
Photosynthesis is a two-step process: • Light reactions – require sunlight energy to split water molecules into 2H and O2 • Calvin Cycle (dark reactions) – hydrogen generated from the light reactions is used to reduce CO2 to generate sugar – does not require sunlight • Leaves absorb CO2 through stomata..
Light Chloroplast NADP ADP + P Calvin cycle Light reactions
Excited state e 1 2 Heat Light (b) fluorescence of isolated chlorophyll in solution Light (fluorescence) Photon Ground state Chlorophyll molecule (a) Absorption of a photon (c) Fluorescence of a glow stick • Chlorophyll molecules absorb photons • Electrons in the pigment gain energy • The energy is released and used..
The light reactions in the thylakoid membrane 2NADP+ 2NADPH2 • 2H2O O2 ..
To Calvin Cycle Light Light ADP + P NADP Stroma Electron transport chain Thylakoid membrane ATP synthase Inside thylakoid 1/2 Light Reactions
The Calvin Cycle: Making Sugar From Carbon Dioxide • The Calvin cycle • Functions like a sugar factory within a chloroplast • Regenerates the starting material with each turn 6NADPH2 6NADP + 12H 6CO2 C6H12O6
Input 3 CO2 3 RuBP 6 3-PGA 6 3 ADP 6 ADP + 6 Calvin cycle 6 3 6 NADP 6 G3P 5 G3P 1 G3P Glucose and other compounds Output
Photosynthesis has an enormous impact on the atmosphere • It swaps CO2 in the atmosphere for O2 Why do we need the O2?..