photosystem

(redirected from PS II)

photosystem

(ˈfəʊtəʊˌsɪstəm)
n
(Botany) botany either of two pigment-containing systems, photosystem I or II, in which the light-dependent chemical reactions of photosynthesis occur in the chloroplasts of plants
References in periodicals archive ?
Tenders are invited for SITC of Potential transformer at PS III and PS IV SITC of Current transformer at PS II for Dr Karni Singh Lift scheme
In our study, Fv/Fm, qL and ETR were decreased under drought stress, indicating that drought stress inhibited the photochemical activity of PS II (Fig.
They describe the multiple roles of various reactive oxygen species in photosynthetic organisms, the structure and function of the water oxidation complex of PS II (water-plastoquinone oxido-reductase), the possible role of Mn-bicarbonate complex in the water oxidation complex, the structural and functional organization of the pigment-protein complexes, the structure and regulation of chloroplast ATP-synthase, the participation of molecular hydrogen in microalgae metabolism, concepts in the evolution and development of photosynthetic carbon metabolism, and the adaptive changes of photosynthesis at increased carbon dioxide concentrations, as well as the photosynthetic machinery response to low temperature stress.
It is concluded that the dissipation of excessive excitation energy in the PS II may be the major protective mechanism to prevent the chloroplast from photodamage.
Research has shown that mutations of the D1 protein in the PS II complex can either increase or decrease photosynthetic activity.
m] ratio expresses the quantum yield of photochemical processes of photosystem, namely the relative efficiency of light energy capture by PS II (BAKER, 2008).
The first case was a 75-year-old man, ASA PS II, with a history of hypertension.
The results demonstrate: (1) conversion of excess excitation energy into heat, called thermal dissipation, limits energy flux through photosystem (PS) II during development of PS II, (2) following development of maximum electron-transport potential within PS II, thermal dissipation decreases allowing for increased photochemical utilization of excitation energy, and (3) changes of the magnitude of thermal dissipation help maintain an optimal, manageable energy flux through the photosystems during the development of photochemistry.
The PS II approach performs very poorly, relative to random sampling, across all three MLRAs.
Many studies have demonstrated abrupt decrease in PS II photochemistry above a threshold temperature (Terzaghi et al,.
PS I and PS II perform different functions based on each having a different kind of reaction center.