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Review. Photosynthetic pigments thought to originally have evolved to protect against UV radiation (like your skin pigments)5 types of bacteria 1 archaea use light energy for some part of metabolismOnly cyanobacteria are oxygenic (chloroplasts derived from them)Prototype Reaction Center perform
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1. Photosynthesis in Cyanobacteria and chloroplasts Macro-evolution to enhance efficiency and overcome stressors
2. Review Photosynthetic pigments thought to originally have evolved to protect against UV radiation (like your skin pigments)
5 types of bacteria + 1 archaea use light energy for some part of metabolism
Only cyanobacteria are oxygenic (chloroplasts derived from them)
Prototype Reaction Center performed both functions:
generate ATP to power metabolism
Reduce NADH+ to NADPH for use in C fixation (electron carrier)
Solutions to low efficiency of intermediate-type reaction center:
RC Type 2: Purple (sulfur and non-sulfur) and filamentous green bacteria have a reaction center that uses cyclic electron flow to synthesize ATP
RC Type 1: Green sulfur bacteria and Heliobacteria have a reaction center that uses non-cyclic electron flow to synthesize NADPH
Linked Photosystems: Cyanobacteria have 2 different types of reaction centers linked together
PS II: similar to RC 2 but instead of recycling e-, passes it to PS I
PS I: similar to RC 1