As an analogy, if bacteria were ants, then a microcolony would be a tiny group of ants, each doing it's own thing, whereas a biofilm would be an ant farm with complex tunnels and rooms, and each ant carrying out a specialized task.
打个比方,如果细菌是蚂蚁的话,菌落就相当于分工明确的蚁群,而生物膜就相当于一个有着复杂通道和小房子的蚂蚁房,其中的每只蚂蚁都有自己特殊的任务。