Chlorophyll b Chlorophyll b Chlorophyll "b" is a form of chlorophyll. Chlorophyll "b" helps in photosynthesis by absorbing light energy. It is more soluble than chlorophyll "a" in polar solvents because of its carbonyl group. Its color is green, and it primarily absorbs blue light. In land plants, the light-harvesting antennae around photosystem II contain the majority of chlorophyll "b". Hence, in shade-adapted chloroplasts, which have an increased ratio of photosystem II to photosystem I, there is a higher ratio of chlorophyll "b" to chlorophyll "a". This is adaptive, as increasing chlorophyll "b" increases the range of wavelengths absorbed by the shade
Photosynthetic reaction centre Photosynthetic reaction centre A photosynthetic reaction center is a complex of several proteins, pigments and other co-factors that together execute the primary energy conversion reactions of photosynthesis. Molecular excitations, either originating directly from sunlight or transferred as excitation energy via light-harvesting antenna systems, give rise to electron transfer reactions along the path of a series of protein-bound co-factors. These co-factors are light-absorbing molecules (also named chromophores or pigments) such as chlorophyll and phaeophytin, as well as quinones. The energy of the photon is used to excite an electron of a pigment. The free energy created is then used to reduce