if chlorophyll a is responsible for light reaction of photosynthesis .why do action and absorbtion spectrum do not overlap
Dear student,
The action spectrum of photosynthesis and absorption spectrum of photosynthesis are similar showing that chlorophylls are the most important pigment for photosynthesis but they are not absolutely identical. This leaves scope for other pigments like chlorophyll b and carotenoids to be also included in the process. As some photosynthesis does takes place at the other wavelengths of the spectrum. Though chlorophyll is the major pigment responsible for trapping light, other thylakoid pigments like chlorophyll b, xanthophylls and caratenoids, which are called accessory pigments. These pigments also absorbs light but transfer the energy to chlorophyll a. Since the absorption spectrum shows which wave lengths are absorbed in each individual type of chlorophyll while the action spectrum shows which wavelengths of light are most effective for photosynthesis.
Regards.
The action spectrum of photosynthesis and absorption spectrum of photosynthesis are similar showing that chlorophylls are the most important pigment for photosynthesis but they are not absolutely identical. This leaves scope for other pigments like chlorophyll b and carotenoids to be also included in the process. As some photosynthesis does takes place at the other wavelengths of the spectrum. Though chlorophyll is the major pigment responsible for trapping light, other thylakoid pigments like chlorophyll b, xanthophylls and caratenoids, which are called accessory pigments. These pigments also absorbs light but transfer the energy to chlorophyll a. Since the absorption spectrum shows which wave lengths are absorbed in each individual type of chlorophyll while the action spectrum shows which wavelengths of light are most effective for photosynthesis.
Regards.