Unformatted text preview: n photosystem II absorbs light, an excited
electron is captured by the primary electron
acceptor, leaving the reaction center oxidized.
2. An enzyme extracts electrons from water and
supplies them to the oxidized reaction center.
– This reaction splits water into two hydrogen ions and an
oxygen atom which combines with another to form O2. - by product of light reactions are ADP and NADP+
which are used to drive the dark reactions Fig. 7.2 7 Fig 7.12 - take water molecules apart
- this releases 2 electrons (one electron per hydrogen)
- use these electrons to replace electron that has been
moved up to higher energy level 3. Photoexcited electrons pass along an
electron transport chain before ending up at
an oxidized photosystem I reaction center.
4. As these electrons pass along the
transport chain, their energy is harnessed
to produce ATP. 8 - light hits PII and the electron is excited and is
grabbed by electron acceptor
- electron is handed off, carrier to carrier, until it can
serve the job of replacing the electron in photosystem i
- it is embedded in the membrane
- PQ is only mobile part See Fig. 7.12 5. At t...
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