ps Flashcards
light reactions make
ATP and NADPH
dark reactions use what to run what
ATP and NADPH to turn pentose phosphate and glycolysis in reverse
E = hc/gamma what are all the variables
h = planck’s constant
c = velocity of light
gamma = wavelength
electron transfer
chemical breakdown by ejection of the excited electron
resonance transfer
transfer of energy to adjacent molecule with same energy gap
why ultraviolet light bad
energy too high, will break covalent bonds
why infrared bad
energy too low, bond rotation and vibration
role of accessory pigment
can harvest more light in the EMS
chlorophylls
magnesium, looks similar to heme-like porphyrin ring
carotenoids
long chian with double bonds flanked by two rings
isoprenoid unit
phycobilins
open chain tetrapyrolls
similar to unwound chlorophylls
phytol side chain
chlorophyll, anchor in membrane
what starts e- flow
light absorption
what type of transfer is antenna molecule passing energy to neighboring chlorophyll molecules
resonance energy transfer
what type of transfer is privileged chlorophyll to electron acceptor
electron transfer
H+ pump
cytochrome b6f complex
1 e- carriers
ferredoxin
plastocyanin
the etc pumps protons from
stroma to lumen
how many photons per electron
one
what is reduced by e- transferred from chlorophyll
ferredoxin
what refills the reaction center “special pair” of chlorophyll molecules
plastocyanin
ps1 cylic flow
light -> p700 -> fd -> cytb6f -> plastocyanin and pumps protons
how many protons pumped per photon cytb6f
2
ps1 wavelength at which chromophore absorbs max
p700
input for cytochrome b6f
plastoquinone PQH2 (PSII) or 2 ferredoxin fd (ps1)
output for cytochrome b6f
2 molecules of plastocyanin (cu) 1 e- carrier
what is cytochrome b6f homologous to
complex 3 of mitochondiral repiratory chain
how are e- replaced in noncylic flow
ps2 uses h2o as e- source to replensih cyt b6f
ps2 wavelength at which chromophore absorbs max
p680
what helps catalyze splitting of water in ps2
mn4 clutster and tyrosine
ps2 equation
2h2o -> 4H+ + 4e- + o2
ps1 + ps2 equation
2 nadp + 3 adp + 3 hpo42- + H + 8 photons -> o2 + 3 atp + 2 NADPH + h2o
how many protons pumped per photon in ps2
1
p side in thylakoid
lumen
n side in thylakoid
stroma
rubscio type of enzyme
carboxylase/oxygenase
ruscio components
Mg2+ complexed to lysine 201 carbamate
rubisco mechanism
enediolate intermediate forms new c-c bond
rubisco octomer
cooperativity
hexose production equation
6 RuBP + 6 CO2 -> 12 (GAP or DHAP)
how many gap and dhap are siphoned off to regenerate rubp
4 gap and 2 dhap
what is needed in regenerating rubp
atp
is there redox in regenerating rubp
no, shuffling carbons
dark reactions equation
6 CO2 + 18 ATP + 12 NADPH + 12 H2O -> C6H12O6 + 18 ADP + 18 HPO42- +12 NADP + 6H
net reaction of photosynthesis
6 co2 + 6 h2o _ 48 photons -> c6h12o6 + 6 o2
photorespiration where
peroxisome via detour thorugh mitochondrion
photorespiration mechanism
reverse of carbon fixation (uses o2 and makes co2)
wasterd rubp must be regenerated
requires atp input
what have c4 plants done
evolved way to concentrate co2 to minimize side reactions
rubisco stimulated by
high pH co2 and mg2+
when reduced fd build up, reduces disulfies to activate DR enzymes
mg2+ moves from ____ to _____
lumen to stroma
H+ move from _____to ______
stroma to lumen
