Most antibiotics function through specific mechanisms that target vital processes in bacterial cells. Commonly, they inhibit cell wall synthesis, protein synthesis, or nucleic acid replication. For instance, penicillin disrupts the formation of the bacterial cell wall, leading to cell death. Others, like tetracyclines, bind to bacterial ribosomes and block protein production. This selectivity allows antibiotics to combat bacterial infections effectively while minimizing harm to human cells. Understanding these mechanisms is crucial for developing new antibiotics and combating resistance.