photosynthesis and cellular respiration, not opposites?

[srm2190]

Ok I've looked over everything I skimmed the tutorial here and I'm still struggling... I need to find out why Photosynthesis and Cellular respiration are NOT the opposite reactions... everything I read and everything I can recall state otherwise (ie. anabolic v. catabolic type reactions, substances on the reactants v. products are opposite, etc) everything is pointing towards opposite but I know that "technically" they are not opposite I just can't remember why!!! It's driving me NUTS!!! I do have a paper due and I really thought I could figure it out before but it's the only question I haven't got answered & I really am just going crazy any help would be really appreciated.

[mith]

respiration doesn't provide light.

[blcr11]

They look like “opposite reactions” only if you consider their net reactions. But these are pathways, not single-enzyme reactions. At least until you get to intermediates that enter central metabolism, the proteins/enzymes/pigments involved in photosynthesis are different from those involved in glycolysis/respiration.

[srm2190]

Thanks! I actually feel silly that I never thought about putting that in there...