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  2. Photosynthetic reaction centre - Wikipedia

    en.wikipedia.org/wiki/Photosynthetic_reaction_centre

    This center, below and to the left of the pair in the diagram, contains four manganese ions, a calcium ion, a chloride ion, and a tyrosine residue. Manganese is adept at these reactions because it is capable of existing in four oxidation states: Mn 2+, Mn 3+, Mn 4+ and Mn 5+. Manganese also forms strong bonds with oxygen-containing molecules ...

  3. Photosynthesis - Wikipedia

    en.wikipedia.org/wiki/Photosynthesis

    The leaf is the primary site of photosynthesis in plants. There are four main factors influencing photosynthesis and several corollary factors. The four main are: [113] Light irradiance and wavelength; Water absorption; Carbon dioxide concentration; Temperature. Total photosynthesis is limited by a range of environmental factors.

  4. Photosystem - Wikipedia

    en.wikipedia.org/wiki/Photosystem

    Reaction centers are multi-protein complexes found within the thylakoid membrane.. At the heart of a photosystem lies the reaction center, which is an enzyme that uses light to reduce and oxidize molecules (give off and take up electrons).

  5. Light-dependent reactions - Wikipedia

    en.wikipedia.org/wiki/Light-dependent_reactions

    The electron transport chain of photosynthesis is often put in a diagram called the Z-scheme, because the redox diagram from P680 to P700 resembles the letter Z. [3] The final product of PSII is plastoquinol, a mobile electron carrier in the membrane. Plastoquinol transfers the electron from PSII to the proton pump, cytochrome b6f. The ultimate ...

  6. Calvin cycle - Wikipedia

    en.wikipedia.org/wiki/Calvin_cycle

    The Calvin cycle, light-independent reactions, bio synthetic phase, dark reactions, or photosynthetic carbon reduction (PCR) cycle [1] of photosynthesis is a series of chemical reactions that convert carbon dioxide and hydrogen-carrier compounds into glucose. The Calvin cycle is present in all photosynthetic eukaryotes and also many ...

  7. Non-photochemical quenching - Wikipedia

    en.wikipedia.org/wiki/Non-photochemical_quenching

    Non-photochemical quenching (NPQ) is a mechanism employed by plants and algae to protect themselves from the adverse effects of high light intensity.It involves the quenching of singlet excited state chlorophylls (Chl) via enhanced internal conversion to the ground state (non-radiative decay), thus harmlessly dissipating excess excitation energy as heat through molecular vibrations.

  8. Endotherm - Wikipedia

    en.wikipedia.org/wiki/Endotherm

    Endotherms control body temperature by internal homeostatic mechanisms. In mammals, two separate homeostatic mechanisms are involved in thermoregulation—one mechanism increases body temperature, while the other decreases it. The presence of two separate mechanisms provides a very high degree of control.

  9. Thermoregulation - Wikipedia

    en.wikipedia.org/wiki/Thermoregulation

    The basal body temperature ranges between 36.7–37.3 °C (98.1–99.1 °F) throughout the luteal phase, and drops down to pre-ovulatory levels within a few days of menstruation. [54] Women can chart this phenomenon to determine whether and when they are ovulating, so as to aid conception or contraception. [citation needed]