As early as 1894, the German chemist Emil Fischer (1852–1919), who was later  awarded the Nobel Prize (Fig. 2.4), postulated that enzymes recognize their sub-  strates on a lock-and-key principle. If the active site of an enzyme lies in a dimple  (cavity, crevice) on the molecule’s surface, the substrate molecule must fit accu-  rately, just like a key into its lock. Even slightly modified molecules will no longer  interact with the enzyme. Lock-and-key is a viable preliminary explanation for the  high substrate specificity of enzymes. It also explains why the shape of competing  enzyme inhibitors (e.g., penicillin) strongly resembles that of the original substrate.  Like a skeleton key, they block the active site of an enzyme (competitive inhibition),  thus preventing the substrate from locking on.

QUESTÃO: O que caracteriza a aula enriquecida por tecnologia? Ainda haverá aulas que não sejam enriquecidas por tecnologia?

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