Purple bacteria produce organic compounds with light energy. This reaction takes place on the...
Question:
Purple bacteria produce organic compounds with light energy. This reaction takes place on the cell membrane, which is folded to increase surface area. No oxygen is produced, but sulfur is produced. Suggest the molecule that provides electrons to the process. Explain your answer.
Anoxygenic Photosynthesis:
While many people commonly associate the process of photosynthesis with the production of O{eq}_2 {/eq}, some photosynthesis, called anoxygenic photosynthesis, occurs without producing O{eq}_2 {/eq}. In fact, many modern day photosynthetic bacteria, including both the purple and green bacteria, are similar to the Earth's first photosynthetic bacteria which were anoxygenic. Ultimately, cyanobacteria, capable of oxygenic photosynthesis which produces O{eq}_2 {/eq}, evolved; their photosynthetic activity resulted in the accumulation of O{eq}_2 {/eq} in the Earth's atmosphere, laying the groundwork for life to evolve based upon an aerobic metabolism.
During oxygenic photosynthesis, O{eq}_2 {/eq} is formed when H{eq}_2 {/eq}O is split, donating its electrons to the electron transport chain embedded in a photosynthetic membrane. During anoxygenic photosynthesis, other reduced molecules, either organic or inorganic, are used as electron donors for this purpose. In either case, photosynthetic bacteria tend to form extensive folding of their photosynthetic membranes (most commonly their cell membranes) to increase the surface area for photosynthesis.
Answer and Explanation: 1
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View this answerPurple bacteria are anoxygenic photosynthesizers, meaning that they use reduced electron carriers other than H{eq}_2 {/eq}O as their electron donors....
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Oxygenic and Anoxygenic Phototrophs: Definition and Examples
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Chapter 24 / Lesson 21
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