What is the relationship between photosynthesis and aerobic cellular respiration? in cellular respiration, what is oxidized and what is reduced? what is the role of electron carrier molecules in energy processing systems? why are they necessary? is glucose the only molecule that can be catabolized during cellular respiration? why do we use glucose as the model? why do hydrogen atoms accompany electrons as they are transferred in biological systems? why is it thought that glycolysis is the first catabolic pathway to have evolved in the metabolism of all cellular systems? can a cell produce enough atp to persist by using glycolysis alone? why or why not? why do anaerobic cellular systems use fermentation? what would happen if they didn’t? why do mammalian muscle cells perform lactic acid fermentation (instead of, say, ethanol fermentation)?