These are terms associated, in particular, with recombinant DNA technology and are therefore presently fashionable. The term "cutting" in this context refers to the hydrolysis of phosphodiester linkages in DNA or RNA, often at base-specific sites along the polymer chain. The single-strand breaks in the phosphodiester linkages that result from hydrolysis reactions catalyzed by restriction enzymes occur either at exactly opposite positions on the two strands to give rise to "blunt ends", or offset at specific palindromic sequences generating "sticky ends". These hydrolysis reactions are exothermic and spontaneous in the thermodynamic sense, as are hydrolysis reactions of nucleic acids and proteins in general. However, these hydrolysis reaction are catalyzed with appropriate enzymes, although RNA does undergo a slow hydrolysis in alkaline solution. The use of the shorthand term "cutting", while emphasizing the significant aspect of the reaction, i.e. breakage of the DNA strand, supports the widespread misconception that it is the bond breaking that produces the energy release. However, those students who have been convinced that bond breaking requires an input of energy, are likely to conclude, as evidenced by responses to exam questions, that the "cutting process" must be endothermic. The term "cutting" tends to disguise the hydrolytic nature of the reaction in which both bond making and breaking are occurring.

    This widely used term is analogous to "cutting ", but with a somewhat longer history, with both referring essentially to the same process. The term "cleavage" is, more often than not, employed in describing the result of a hydrolysis reaction. The term "hydrolytic cleavage", in this case, is also frequently encountered, and is less ambiguous.

    This phrase tends to be encountered in general chemistry texts but can be found in physical chemistry texts as well. It represents as with the other terms listed here, a convenient shorthand for a process that demands a more lengthy description to appreciate. Consider the following situation. A non-chemist interested in the environment and energy sources in the future, asks a chemist why hydrogen represents a good fuel. They understand that the molecule is simply composed of two hydrogen atoms bonded together, and want to know where the energy comes from. The response, without further elaboration, could well be that "the energy is stored in the bond". It is not difficult to imagine that the non-chemist would conclude that "if the energy is stored in the bond", then if there were no bond there would be no energy. It would seem entirely reasonable to conclude that energy release associated with hydrogen as a fuel must derive from breaking the bond. A distinctly clearer response would require that it be pointed out that good chemical fuels involve molecules in which the bonds holding them together are relatively weak, so that in reactions, e.g. involving oxygen (O2(g)), those weaker bonds are replaced by stronger ones in the products, water (H2O) in the case of the combustion of hydrogen.

    It is not difficult to understand why it is often suggested that students would be better off if left with their inconsistencies; i.e. to live with the convenient misconception that bond breaking is exothermic in their biology courses, but endothermic when dealing with problems in chemistry. There are, however, inconsistencies in this matter within biology itself. Retaining the misconception that the rupture of , e.g. the high-energy phosphate bond is exothermic, more often than not, it would.be conceded that the rupture of H-bonding in the denaturation of DNA or the melting of ice, does requires an input of energy.