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Chloride shift (also known as the Hamburger phenomenon or lineas phenomenon, named after Hartog Jakob Hamburger) is a process which occurs in a cardiovascular system and refers to the exchange of bicarbonate (HCO 3 −) and chloride (Cl −) across the membrane of red blood cells (RBCs).
The isolated reaction of anabolism is unfavorable in a cell due to a positive Gibbs free energy (+ΔG). Thus, an input of chemical energy through a coupling with an exergonic reaction is necessary. [ 1 ] : 25–27 The coupled reaction of the catabolic pathway affects the thermodynamics of the reaction by lowering the overall activation energy ...
Redox reactions are chemical reactions in which electrons are transferred from a donor molecule to an acceptor molecule. The underlying force driving these reactions is the Gibbs free energy of the reactants relative to the products. If donor and acceptor (the reactants) are of higher free energy than the reaction products, the electron ...
Metabolism (/ m ə ˈ t æ b ə l ɪ z ə m /, from Greek: μεταβολή metabolē, "change") is the set of life-sustaining chemical reactions in organisms.The three main functions of metabolism are: the conversion of the energy in food to energy available to run cellular processes; the conversion of food to building blocks of proteins, lipids, nucleic acids, and some carbohydrates; and the ...
During the first phase, it requires the breakdown of two ATP molecules. [1] During the second phase, chemical energy from the intermediates is transferred into ATP and NADH. [2] The breakdown of one molecule of glucose results in two molecules of pyruvate, which can be further oxidized to access more energy in later processes. [1]
Chemiosmosis is the movement of ions across a semipermeable membrane bound structure, down their electrochemical gradient. An important example is the formation of adenosine triphosphate (ATP) by the movement of hydrogen ions (H +) across a membrane during cellular respiration or photosynthesis.
In forward movement, the long axis of the cell, the flagellar bundle and the direction of movement are aligned, and propulsion is similar to the propulsion of a freely swimming cell. In a reversal, the flagellar bundle loosens, with the filaments in the bundle changing from their "normal form" (left-handed helices) into a "curly" form of right ...
The phenomenon of bidirectional movement has been demonstrated by applying two different substances at the same time to the phloem of a stem at two different points, and following their longitudinal movement along the stem. If the mechanism of translocation operates according to pressure flow hypothesis, bidirectional movement in a single sieve ...