photosynthesis Flashcards
what is an autotroph
organisms that can make organic molecules(glucose) from inorganic molecules (co2). they also use light or chemical energy to do this
what is a heterotroph?
organisms that have to obtain organic molecules(glucose) that have been made by another organism(eat plants or animal matter-secondary, tertiary , quaternary consumers)
what is a light dependant reaction
energy s absorbed from sunlight
atp is made
hydrogen from water is used to form reduced atp
what’s a light independent
hydrogen from reduced naps and co2 is used to build organic molecules
atp is needed
explain the steps of the calvin cycle(LIR)
1.the enzyme rubisco adds CO2 to RUBP (5c)to make GP(3c)
2.GP is reduced to TP using ATP for energy (from LD)aswell as NADPH which provide H+ to make the TP
3)5/6 f the TP made is converted aback to PUP which is then given another phosphate form ATP to make RUBP
4) the 1/6 left of TP made is used to make carbs, amino acids, cellular ect
RUBP meaning
Ribulose Bisphosphate
meaning of GP
Glycerate 3-Phosphate
TP meaning
Triose Phosphate
RUP meaning
Ribulose Phosphate
explain the steps of the light dependant reaction
1.light hits the photo system 2 and excited 2 electrons which leave chlorophyll
2.and pass down the electron transport chain
3.the electrons release energy that pumps H+ into the thylakoid space
4.light then hits photosystem 1 and then excited 2 electrons which leave chlorophyll and pass down electron transport chain and are accepted by NADP
what is photolysis and how does it link to LD
ps2 has an enzyme that in light performs photolysis of water forming 2H+2e&1/2O2. The 2e/ reduce the oxidised chlorophyll in ps2 that had originally lost electrons
what happens differently in a cyclic Light dependant reaction
the 2 excite electrons wave ps1 but pass back down the electron transport chain, creating no atp and no photolysis and no NADP
