(couleur) grey (Grande-Bretagne) , gray (USA) il fait gris it's a dull day, it's a grey day. faire grise mine to look morose. faire grise mine Ã  qn to give sb a cool reception.
In electrophilic aromatic substitution, the benzene ring acts as an electron donor (Lewis base or nucleophile) and reacts with an electron acceptor (Lewis acid or electrophile). The result of electrophilic aromatic substitution reactions is that an aromatic hydrogen is replaced by some other atom or functional group.
Role of FMN: Since it can accept/donate either 1 or 2 e- , FMN has an important role in mediating electron transfer between carriers that transfer 2 e - (e.g., NADH) and carriers that can only accept 1 e - (e.g., Fe +++). See discussion of complex I below.