The Photosynthesis-Light Response Curve

Abstract

Instantaneous rates of photosynthesis may be controlled by external factors, including irradiance, temperature, and the concentrations of CO₂ and O₂, by the molecular composition of the photosynthetic apparatus, including the concentrations or activities of pigments, catalysts of electron transport, and enzymes of CO₂ fixation, or by other factors, such as the concentration of metabolites, or the demands for photosynthetic products. Photosynthesis-factor response curves, such as the photosynthesis—irradiance, photosynthesis—CO₂, and photosynthesis—temperature relations describe the response of photosynthesis rates to external factors. In addition, the interpretation of these curves often provides important information on regulatory control of photosynthesis by the composition of the photosynthetic apparatus and other internal factors.