Differentiate between Chlorophyll A and Chlorophyll B ?

Difference between the Chlorophyll A and Chlorophyll B:

Ans. CHLOROPHYLL A AND CHLOROPHYLL B:

Chlorophyll A

Chlorophyll B

(i) Functional Groups bonded to the porphyrin carbonyl group (-CHO)

(ii) Molecular formulae C55H72O5N4Mg.

(iii) Some wave lengths not absorbed by chlorophyll B which effectively absorbed by Chlorophyll A.

(iv) Chlorophyll A is blue-green.

(v) Of all the chlorophylls, Chlorophyll A is the most abundant.

(vi) Most important photosynthetic pigment as it takes part directly in the light-dependent reaction which converts solar energy to chemical energy.

(vii) It initiate light reaction.

(viii) It has many forms which differ slightly in red absorbing peaks (e.g. at 670, 680, 690, 700 nm)

(ix) Insoluble in water but soluble in organic solvents (such as carbon tetrachloride alcohol).

(x) It is found in all photosynthetic organisms except photosynthetic bacterial.

(i) Functional Groups bonded to the porphyrin methyl group (-CH3)

(ii) Molecular formulae C55H70O6N4Mg.

(iii) Some wave lengths not absorbed by chlorophyll A which effectively absorbed by Chlorophyll B.

(iv) Chlorophyll B is yellow-green.

(v) Less abundant.

(vi) Chlorophyll B transfer energy to the Chlorophyll A.

(viii) It has the accessory pigment because it absorbs light and transfer the energy to chlorophyll A.

(ix) It has only one form.

(x) It is found with chlorophyll A in all green plants (Embryophytes) and green algae.

Due to this slight difference in their structure, the two chlorophylls show slightly different absorption spectra and hence different colours.

Such differences in structure of different pigments increase the range of wavelength of the light absorbed.