Photosynthetic pigments
Chlorophyll a -> main photosynthesising pigment involved in light dependent stage
made up of porphyrin ring with magnesium centre and hydrocarbon tail
absorbs blue-violet and red-orange light(visible spectrum only)
magnesium ion gets excited when one of its electrons gets energy from a photon
releases an excited electron to primary acceptor molecule
Accessory pigments - chlorophyll b, xanthophyll + carotene(carotenoids) and
phaeophytin
light-harvesting pigments + used to increase range of wavelengths absorbed to be
used in photosynthesis
Not involved in photosynthesis
Transfer energy absorbed to chlorophyll a to be used in photosynthesis
Absorption spectrum: wavelengths of light that a particular photosynthetic pigment
absorbs(graph of absorbance)
Action spectrum: wavelengths of light that bring about photosynthesis in a particular
plant (graph of rate of photosynthesis)
Pigments arranged in photosystems in thylakoid membranes
pigment molecules are clustered into antenna complexes
arranged in a complex to channel light energy to one molecule of chlorophyll a
Chlorophyll a + primary acceptor molecule = reaction system
Photosystem = reaction centre + other light harvesting molecules
, 2 types of photosystem: P1 and P2
P1 = reaction centre is called P700 - chlorophyll a max absorption of 700nm(red)
P2 = reaction centre is P680 - chlorophyll a max absorption of 680nm(orangey red)
work together in light-dependent stage
PS1 = NADPH producing
PS2 = water splitting
Light-Dependent stage
occur in thylakoid membranes in grana
ADP converted to ATP - Photophosphorylation
Water molecules split into H+ and O2 - Photolysis
NADP reduced to NADPH
1. Photons from sunlight excite magnesium particles in chlorophyll a in photosystem 2
high energy state + electron leaves chlorophyll molecule
The benefits of buying summaries with Stuvia:
Guaranteed quality through customer reviews
Stuvia customers have reviewed more than 700,000 summaries. This how you know that you are buying the best documents.
Quick and easy check-out
You can quickly pay through credit card for the summaries. There is no membership needed.
Focus on what matters
Your fellow students write the study notes themselves, which is why the documents are always reliable and up-to-date. This ensures you quickly get to the core!
Frequently asked questions
What do I get when I buy this document?
You get a PDF, available immediately after your purchase. The purchased document is accessible anytime, anywhere and indefinitely through your profile.
Satisfaction guarantee: how does it work?
Our satisfaction guarantee ensures that you always find a study document that suits you well. You fill out a form, and our customer service team takes care of the rest.
Who am I buying these notes from?
Stuvia is a marketplace, so you are not buying this document from us, but from seller juliapurrinosdeoliveira. Stuvia facilitates payment to the seller.
Will I be stuck with a subscription?
No, you only buy these notes for £6.49. You're not tied to anything after your purchase.
