Chlorophyll b

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Chlorophyll b
Structure of β-Chlorophyll
CAS number 519-62-0 YesY
PubChem 6450186 YesY, 11593175 (from spinach) YesY
ChemSpider 16739843 YesY
UNII 5712ZB110R YesY
EC-number 208-272-4
Jmol-3D images Image 1
Molecular formula C55H70MgN4O6
Molar mass 907.47 g mol−1
Appearance Green
Odor Odorless
Melting point ~ 125 °C (257 °F; 398 K)[1]
Solubility in water Insoluble[1]
Solubility Very soluble in EtOH, ether, C5H5N
Soluble in MeOH[1]
Absorbance See text
Except where noted otherwise, data are given for materials in their standard state (at 25 °C (77 °F), 100 kPa)
 YesY (verify) (what is: YesY/N?)
This is the Absorption Spectrum of both the Chlorophyll a and the Chlorophyll b pigments. The use of both together enhances the size of the absorption of light for producing energy.

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 yellow, and it primarily absorbs blue light.[2]

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 lower ratio of chlorophyll a to chlorophyll b (Kitajima and Hogan 2003). This is adaptive as increasing chlorophyll b increases the range of wavelengths absorbed by the shade chloroplasts.

Structure of Chlorophyll b molecule showing the long hydrocarbon tail