Loudoun County Public Schools€¦ · Why do leaves change color in the fall? Chlorophyll begins to...

Pigments

The primary pigment is chlorophyll a in green plants and

bacteriochlorophyll in bacteria These absorb mostly red, blue, and

violet pigments

Absorption of Light by Chlorophyll a and Chlorophyll b

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Chlorophyll b

Chlorophyll a

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Wavelength (nm)

Types of Pigments (light absorbing compounds)

1.Chlorophyll a: Primary pigment responsible for photosynthesis.

Absorbs light in the ma, violet and blue regions of the visible spectrum

and reflects blueish-green light which is why plants look green.

2.Chorophyll b: Absorbs light in the .atd and blue regions of the visible

spectrum and reflects ., . -green light which is why plants lookgreen.

3.Carotenoids: (Carotene & Xanthophyll) Accessory pigments that

absorbs green and blue hues and reflects and orange.

4.Anthocyanins: Accessory pigments that absorbs green, � and

orange hues and reflects md., violet and blue.