What is meant by OXIDATION and REDUCTION?!
In my experience, these two concepts often give students a great deal of trouble. Oxidation and reduction reactions (also known as REDOX reactions) are always coupled in biological systems. Put quite simply, oxidation reactions release energy. Compounds that contain the greatest amount of stored chemical energy are hydrocarbons such as fats and lipids. In biological systems, oxidation typically involves: • the loss of hydrogen atoms (equivalent to protons) from a substrate • loss of hydrogen atoms are known as dehydrogenation reactions • electrons are typically lost together with hydrogen atoms • the addition of oxygen is also termed oxidation • an “oxidized” molecule has given up energy. For example, the energy carrier molecule NAD+, is an energy-deficient form of an electron carrier as it has given up a hydrogen and two electrons. Reduction reactions harness chemical energy. Reduction involves: • the gain of electrons and hydrogen atoms by a substrate. This is what confuses people; h
