Ch. 22 Photosynthesis Flashcards
Where does resonance energy transfer occur?
Between antennae chlorophylls to reaction center
Where does photo-induced charge separation occur?
Within the reaction center
What is resonance energy transfer?
An electron accepts energy from light and jumps to a higher energy level, when it jumps back down, it transfers energy to another electron. Passes energy to the reaction center
What is photo-induced charge separation?
When an excited electron moves to a nearby molecule with a lower exicted state
What are the charges of the molecules after photo-induced charge separation?
Initial molecule: + charge
Acceptor molecule: - charge
Where does photosynthesis take place?
In the thylakoid membranes within chloroplasts
What colors of light does chloryphyll absorb?
Purple/blue
Orange
Which photosystem generates NADPH?
Photosystem 1
Which photosystem oxidizes water?
Photosystem 2
What is the reaction center in Photosystem 2?
p680
What is the reaction center in Photosystem 1?
p700
What is the path of electrons from water to NADH in photosynthesis?
Light splits water into O2 in the water oxidizing complex of photo2
Electrons flow from Photo2 through Cytochrome b6f to Photo1
Cytochrome b6f generates proton motive force for ATP synthesis
Electrons in Photo1 flow to ferredoxin
Ferredoxin-NADP+ reductase generates NADPH
What membrane components contribute to the proton gradient?
Cytochrome b6f- 8H+
Water oxidation complex- 4H+
What is the net reaction of photosynthesis?
8 photons + 2NADP+ + 3ADP + 3Pi + H+ >
O2 + 2NADPH + 3ATP +H2O
What is cyclic photophosphorylation?
Electrons from Photo1 flow from ferredoxin through cytochrome b6f (rather than reductase) to platocyanin then return to p700 to produce ATP without producing NADH
