Energy tends to disperse spontaneously (second law thermodynamics) ENTROPY is a measure of how much the energy of a system is dispersed.
METABOLIC PATHWAY; Cells build, convert, and dispose of substances in enzyme-mediated reaction, cells store and retrieve free energy by making and breaking chemical bonds in metabolic reaction, in which REACTANT are converted to PRODUCT in the cytoplasm.
ENDERGONIC reactions require a net energy input.
EXERGONIC reactions end with a net energy release.
ACTIVATION ENERGY; is the minimum energy required to start a reaction.
ALLOSTERIC sites are points of control by which a cell adjust the types of amounts of substances it makes. FEEDBACK INHIBITION is an example of enzyme control.
REDOX; (oxidation-reduction) reactions in electron transfer chains allow cells to harvest energy in manageable increment.
ATP functions as an energy carrier between reaction sites in cells. It has three phosphate bonds, when a phosphate-group is transferred to another molecule; the energy of the bond is transferred along with it.
CELL MEMBRANE is a mosaic of proteins and lipids (mainly phospholipids) function of all cell membranes have transport proteins, incorporate receptor proteins, adhesion proteins, enzymes, and recognition proteins.
OSMOSIS; is the diffusion of water across a selective permeable membrane/ lower solute