| transition [tran`zish·ǝn] COMMUNICATIONS Change from one circuit condition to the other; for example, the change from mark to space or from space to mark. MOLECULAR BIOLOGY A mutation resulting from the substitution in deoxyribonucleic acid or ribonucleic acid of one purine or pyrimidine for another. QUANTUM MECHANICS The change of a quantum-mechanical system from one energy state to another. THERMODYNAMICS A change of a substance from one of the three states of matter to another. |