Search results
Results From The WOW.Com Content Network
For an N-particle system in three dimensions, a single energy level may correspond to several different wave functions or energy states. These degenerate states at the same level all have an equal probability of being filled. The number of such states gives the degeneracy of a particular energy level. Degenerate states in a quantum system
Light-dependent reactions of photosynthesis at the thylakoid membrane. Light-dependent reactions are certain photochemical reactions involved in photosynthesis, the main process by which plants acquire energy. There are two light dependent reactions: the first occurs at photosystem II (PSII) and the second occurs at photosystem I (PSI).
Photoexcitation is the first step in a photochemical process where the reactant is elevated to a state of higher energy, an excited state.The first law of photochemistry, known as the Grotthuss–Draper law (for chemists Theodor Grotthuss and John W. Draper), states that light must be absorbed by a chemical substance in order for a photochemical reaction to take place.
24% of the absorbed photon energy is lost due to degrading short wavelength photons to the 700 nm energy level; 68% of the used energy is lost in conversion into d-glucose; 35–45% of the glucose is consumed by the leaf in the processes of dark and photo respiration; Stated another way: 100% sunlight → non-bioavailable photons waste is 47% ...
Photosensitization is a process of transferring the energy of absorbed light. After absorption, the energy is transferred to the (chosen) reactants. This is part of the work of photochemistry in general. In particular this process is commonly employed where reactions require light sources of certain wavelengths that are not readily available. [14]
In 2011 the OEC of PSII was resolved to a level of 1.9Å revealing five oxygen atoms serving as oxo bridges linking the five metal atoms and four water molecules bound to the Mn 4 CaO 5 cluster; more than 1,300 water molecules were found in each photosystem II monomer, some forming extensive hydrogen-bonding networks that may serve as channels ...
The faster reactions involve the transfer of an electron from BPh − (BPh − is oxidized to BPh) to the electron acceptor quinone (Q A), and the transfer of an electron to P960 + (P960 + is reduced to P960) from a heme in the cytochrome subunit above the reaction center. The high-energy electron that resides on the tightly bound quinone ...
Energy in the form of sunlight; The light dependent reactions take place when the light excites a reaction center, which donates an electron to another molecule and starts the electron transport chain to produce ATP and NADPH. Once NADPH has been produced, the Calvin cycle [1] proceeds as in oxygenic photosynthesis, turning CO 2 into glucose.