Assess understanding of photosynthesis with emphasis on the light-dependent reactions (photon capture, electron transport chain, photolysis, ATP/NADPH production), the Calvin cycle (RuBisCO-mediated carbon fixation, reduction to G3P, RuBP regeneration), and how environmental factors (light intensity and wavelength, CO2 concentration, temperature, water availability) affect overall rate; require mechanism-level explanations and prediction of limiting steps.