Pigments Flashcards
1
Q
what are photosynthetic pigments?
A
-photosynthetic pigments absorb light energy
- each pigment absorbs a range of wavelengths in visible region of the electromagnetic spectrum and has its own distinct peak of absorption.
- other wavelengths are reflected
2
Q
what are primary pigments?
A
- the most abundant pigment chlorophyll which exists in 3 forms
3
Q
what are the 3 forms of the pigments?
A
- chlorophyll a (2 types)
- chlorophyll b
4
Q
what colour light does chlorophyll absorb and reflect?
A
- absorbs red light and blue light
- it reflects green light
5
Q
what does it mean if the chlorophyll is the most abundant?
A
- That the leaves appear green
6
Q
what does the primary pigment molecule consist of?
A
a porphyrin group- similar to haem found in haemoglobin only with a magnesium atom at it centre instead of iron
- a long phytol chain
7
Q
what are accessory pigments?
A
- they do not contain a porphyrin group
- these pigments absorb wavelengths of light which poorly absorbed by chlorophyll
- they absorb green light
- this means that the light energy which would otherwise be reflected can also be harvested
8
Q
example of accessory pigments?
A
carotene (orange)
xanthophyll (yellow)
