Excited chlorophyll in the reaction center acts as a reducing agent for electron transport

Ultimately, photosynthesis stores chemical energy by using the excited chlorophyll molecule in the reaction center as a reducing agent to reduce a stable electron acceptor (Figure 8.8). Ground-state chlorophyll (symbolized Chl) is not much of a reducing agent, but excited chlorophyll (Chl*) is a good one. To understand the reducing capability of Chl*, recall that in an excited molecule, one of the electrons is zipping around in an orbital farther away from its nucleus. Less tightly held, this electron can be passed

Reaction Center Chlorophyll
Antenna system embedded in thylakoid membrane

8.8 Energy Transfer and Electron Transport Rather than being lost as fluorescence, energy from a photon may be transferred from one pigment molecule to another, preserving the energy for biochemical work. In an antenna system, an excited pigment molecule can transfer energy through a series of other pigment molecules to a chlorophyll molecule in the reaction center. That molecule may become sufficiently excited that it gives up its excited electron, which can then be passed on to an electron carrier.

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Essentials of Human Physiology

Essentials of Human Physiology

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Responses

  • MARSHALL
    Are xerophytes suitable for chromatography for chlorophyll?
    8 years ago
  • Ami
    Is a chlorophyll a reducing agent?
    8 years ago

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