Photosynthesis

• - 2 membranes
•   > inner membrane
•   > outer membrane 

- Stroma: is the cytoplasm inside of the chloroplast 

• - Chlorophyll: absorbs blue light 
•   > inside of thylakoid

def: disk shape, membranous sac in chloroplast 

• - each disk is called granum 
•   > pigments around absorb diff. wave lenghts
• - contains pigments
•   > some of them arranged into photocentres

Lumen:  space inside of the granum

• - comes mostly from atmospheric CO₂
•   >minerals absorbed through plant tissues

• Chlorophyll A: plants, cyanobacteria
•   > convert light energy to chemical energy

• Chlorophyll B: accessory pigment
•   > absorbs photons of different energy than A 

• short wavelength = higher energy photons
• long wavelength = low energy photons

Photosynthesis can be divided into light-dependent and light-independent reactions. 

CO₂+H₂O+light=(CH₂O)_n+O2

n= represents any #

• chlorophyll A
• absorbs 680 nm
• H₂O is oxidized 
• generates H⁺ gradient

• chlorophyll A
• absorbs 700 
• reduces NADP+
• ATP is produced

• Light strikes chlorophyll in the antenna complex. 
• Pigment molecules in the antenna complex transmit energy to each other. 
• Once energy is transmitted to the reaction center P_{680 chlorophyll A}, an e^- is raised to a higher valence shell. This e- is donated to quinone (bcomes reduces) 
• Water oxidized  in the reaction center P_{680 chlorophyll A.}
• The e- in the quinone is transmitted to b₆f.
• b₆f grabs H⁺ from stroma and pump it into the lumen. The H⁺ pump in goes to the ATP synthase.
• The e- in b₆f is transmitted to the cyanin where it waits to the photon 700 to give to the next pump an electron that is transmitted further in PSI. Then the e- in b₆f enters to the next pump.

• Photon 700nm (light energy) hits the chlorophyll, an e^- is raised to higher valence shell and the e^- is donated to the Ferredoxin. 
• After this donation occur the e- waiting in PSII is then transmitted to the chlorophyll. 
• The e- in ferredoxin (Fd) then is transmitted to the reaction centre.  
• In the reaction centre the e^- reduce NADP giving NADPH. 
• ATP synthase is side to the reaction centre.

Uses e- from PSII to reduce reaction centre absorbs lower-energy photons, uses energy to drive NADPH production in the stroma

• Uses e- from H2O to reduce reaction centre.
• Absorbs higher-energy photons, uses energy to create a proton gradient to drive ATP synthesis. 
• Both PS are interlinked and both require light. 
• End result: ATP and NADPH produced in the chloroplast stroma, O₂ produced from H₂O

• Glucose is the high energy molecule @end of photosynthesis.
• e- is energized in the reaction centre.
• ATP n NADPH made during light reactions
• Cellular respiration starts w the end product of photosynthesis(NADPH n O₂).