Chloroplasts are the sites within plants where this process changes light into chemical energy
[DOC] [TLE] Chemistry for Biologists: Photosynthesis [PAR] The conversion of usable sunlight energy into chemical energy is associated with 
the action of the ... Several modifications of chlorophyll occur among plants and 
other ... of light to make energy-carrier molecules that are used in the second 
process: ... changing it from its oxidised state (NADP+) to its reduced state (
NADPH):.