Cephalosporins are a class of antibiotics that work by inhibiting the synthesis of the bacterial cell wall. The cell wall is essential for the structural integrity of bacteria, and by inhibiting its synthesis, cephalosporins weaken the cell wall, leading to the death of the bacteria. This mechanism of action is effective against a wide range of bacterial infections. In contrast, inhibiting nucleic acid replication and transcription or protein synthesis are mechanisms of action associated with other classes of antibiotics, not cephalosporins.