Читать книгу Molecular Mechanisms of Photosynthesis - Robert E. Blankenship - Страница 16

It is convenient to divide photosynthesis into four distinct phases, which together make up the complete process, beginning with photon absorption and ending with the export of stable carbon products from the chloroplast. The four phases are as follows: (1) light absorption and energy delivery by antenna systems, (2) primary electron transfer in reaction centers, (3) energy stabilization by secondary processes, and (4) synthesis and export of stable products.

The terms light reactions and dark reactions have traditionally been used to describe different phases of photosynthetic energy storage. The first three phases that we have identified make up the light reactions, and the fourth encompasses the dark reactions. However, this nomenclature is somewhat misleading, in that all the reactions are ultimately driven by light, yet the only strictly light‐dependent step is photon absorption. In addition, several enzymes involved in carbon metabolism are regulated by compounds produced by light‐driven processes. We will now briefly explore each of the phases of photosynthetic energy storage, with the emphasis on the basic principles. Much more detail is given in the later chapters dedicated to each topic.