Submitted to: Light as an Energy Source
Publication Type: Book / Chapter
Publication Acceptance Date: June 22, 1995
Publication Date: N/A
Technical Abstract: The photosynthetic membranes of plants perform a remarkable feat, they convert a portion of the energy available in light into chemical free energy. In this way photosynthetic membranes provide a stable form of energy that can be used at later times for energy-requiring biochemical processes, such as the reduction of carbon dioxide to carbohydrate. The first step in photosynthetic energy transformation is the absorption of light by the antenna array, resulting in the conversion of the transient energy stored in electromagnetic radiation into the excited state of pigment molecules. The excited state energy residing in the antenna system is short lived and must migrate rapidly to reaction center complexes, where it drives primary charge separation. The energy stored in the reaction centers by charge separation drives a series of oxidation/reduction reactions within the thylakoid membrane that ultimately converts the energy into the chemical free energy of ATP and NADPH. In this introductory overview we have two goals. The first is to introduce the players, i. e., the components of the chloroplast thylakoid membrane that are responsible for the basic reactions of photosynthetic electron transfer and energy transduction. The second is to track the energy transformations that ultimately result in the conversion of light energy into stable chemical forms.