Photosynthesis Flashcards
Photosynthesis
the process by which light energy is transformed into carbon energy, occurs in chloroplasts
stroma
chloroplast’s cytoplasm
Thylakoids
hollow membrane disks in the chloroplast
thylakoid lumen
space inside thylakoids
grana
stacks of thylakoids
light reactions
use two photosystems to capture light and generate high energy electrons
photosystem II
donates high energy electrons to an ETC, starting with PQ
PQ
reduces cytochrome complex which uses energy from the electrons to pump H+ into the lumen, which generates an H+ gradient across the thylakoid membrane
PC
the last step in the ETC, reduced by low energy electrons
Photosystem I
Accepts the low energy electrons from PC and makes them high energy electrons again, then reduces feridoxin (FD)
feridoxin
delivers the high energy electrons to the enzyme NADP+ reductase to reduce the final electron acceptor, making the high energy electron carrier NADPH
NADP+
final electron acceptor in light reactions
ATP Synthase
enzyme complex powered by the H+ gradient made in the ETC, forms ATP in the stroma (photophosphorylation) and/or matrix (chemiosmosis)
photolysis (PSII)
splitting of water by PSII, which results in new electrons being obtained, restarting the ETC
Calvin Cycle
fixes inorganic carbon from CO2 in the form of organic carbon chains, storing energy in chemical bonds. occurs in stroma
