What can we conclude from the statement that the action and absorption spectra of photosynthesis overlap? At which wavelength, do they show peaks?
The absorption spectrum is the graph plotted, with the amount of light absorbed as a function of wavelength. The action spectrum is the graph plotted with the rate of photosynthesis as a function of wavelength. Since, the amount of light absorbed and the rate of photosynthesis have a direct relationship, the two curves overlap. They show peaks around wavelengths 450 nm (blue region) and 650-680 nm (red region).