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  • photosynthesis
  • The ecophysiological basis for co-variability in light-limited and saturated rates of phytoplankton photosynthesis. (southampton.ac.uk)
  • 2. 2.1 Light-Dependent Cyclic Redox Chain of Purple Bacteria Let us start not from that main (oxygenic) photosynthesis that has just been mentioned above, but from the more primitive photosynthetic mechanisms that have been described in phototrophic bacteria (they have already been mentioned in the Chap. 1). (slideshare.net)
  • Our findings suggest that the symbiotic interaction has resulted in a shift of transcriptional regulation to coordinate UCYN-A metabolism with that of the phototrophic eukaryotic host, thus allowing efficient coupling of N 2 fixation (by the cyanobacterium) to the energy obtained from photosynthesis (by the eukaryotic unicellular alga) in the light. (asm.org)
  • The intent in this chapter is to present a historical perspective of the two major functions of carotenoids in photosynthesis, namely light harvesting and photoprotection, with emphasis on the former. (illinois.edu)
  • The personal perspective of Duysens (1989) provides an account of the discovery of the two light reactions of photosynthesis, necessary for understanding the context of the present day view of photosynthesis. (illinois.edu)
  • Regulatory reactions providing the photosynthetic apparatus with the ability to respond to variations of irradiance by changes in activities of the light and the dark stages of photosynthesis within a time range of seconds and minutes are considered in the review. (springer.com)
  • energy
  • 3. What dictates the efficiency of the flow of energy from light to biomass through the marine ecosystem? (southampton.ac.uk)
  • Moreover, a system that can perform multiple turnovers is required, because even the energy contained in a single photon of visible light is not sufficient for many biochemical reactions. (schoolbag.info)
  • At the heart of this solar energy conversion process are two light-induced electron transfer reactions that generate oxidizing and reducing agents and a transmembrane proton concentration gradient. (schoolbag.info)
  • Phototrophic bacteria use light as the energy source to produce phosphate bond energy (ATP) and reductants [e.g. (frontiersin.org)
  • The energy and reducing equivalents generated from light-induced electron transport drive diverse carbon metabolic pathways for producing cellular material, bioactive products and biofuel. (frontiersin.org)
  • For instance, when using an ultrafast laser one can generate a 2 9 10-14 s long flash of light so as to study kinetics and mechanisms of the primary processes of light energy storage. (slideshare.net)
  • It can be viewed as the operating efficiency of PSII, reflecting the proportion of light energy absorbed by PSII that subsequently drives photochemistry. (carnegiescience.edu)
  • At the light stage, such reactions are related to the changes in both distribution of light energy between two photosystems and probability of nonphotochemical dissipation of absorbed quanta in PSI and PSII. (springer.com)
  • PSII
  • Prior to performing this fluorescence measurement, algal samples are incubated for 10 min in the dark and then exposed to 10 min of far-red light (activating PSI photochemistry) in order to make sure that PSII (and the PQ pool) is fully oxidized and that the cells are in state 1 prior to the measurement. (carnegiescience.edu)
  • qP measures photochemical quenching, providing information about the proportion of PSII reaction centers that are available for photochemistry after exposure of the cells to different light intensities (they are grown at one light intensity and then exposed to various intensities for 5-10 min). (carnegiescience.edu)
  • If the qP values in mutant cells are comparable to those of wild-type cells, it is likely that the mutants are able to acclimate to the various light conditions used for growth and that the extent to which PSII traps remain opened is optimal. (carnegiescience.edu)
  • ΦPSII is related to qP and indicates the photochemical yield of PSII at different light intensities. (carnegiescience.edu)
  • Absorption
  • Absorption of visible light by a chromophore molecule is known to induce transfer of an electron from the main orbital (S0) to one of the singlet (S1 * , S2 * …) or triplet (T) excited orbitals (Fig. 2.2). (slideshare.net)
  • complex
  • The ligand-only view of the crystal structure reveals a picture that should be somewhat familar now: a host of antennae molecules forming a light-harvesting complex. (csbsju.edu)
  • quantum
  • This process is initiated by a quantum of light, and this fact makes it possible to use modern physical instru- mentation for the analysis of its mechanism. (slideshare.net)
  • dark
  • 4) Gas exchange measurements, including both O2 evolution (in the light) and uptake (in the dark), using a Clark-type O2 electrode. (carnegiescience.edu)
  • cells
  • Conversely, low values relative to wild-type cells would suggest that a high proportion of the traps are closed and that the cells are potentially aberrant in their ability to properly acclimate to the light environment. (carnegiescience.edu)