photosynthetic pigments

what are photosynthetic pigments?

molecules that absorb light energy for photosynthesis

where are photosynthetic pigments found?

in thylakoid membranes

how are photosynthetic pigments arranged?

in structures called photosystems

what are the two main photosystems?

• photosystem I (PSI)

• photosystem II (PSII)

what wavelength of light does PSI absorb?

700nm

what wavelength of light does PSII absorb?

680nm

what lights do chlorophyll a and b absorb and reflect?

• absorb red

• reflect green

what lights do xanthophyll and carotene absorb and reflect?

• absorb blue

• reflect orange/yellow

what pigment group are xanthophyll and carotene in?

carotenoids

suggest and explain the advantage of having different coloured pigment in leaves (2)

• different pigments absorb different wavelengths of light

• for photosynthesis

what is an advantage to a plant which lives underwater of having accessory pigments? (2)

• more wavelengths of light can be absorbed

• so more photosynthesis can occur at low light intensities