Final answer:
Beta-lactam antibiotics target the cell wall of bacteria by disrupting the synthesis of peptidoglycan, which is essential for bacterial growth and protection, but not present in human cells.
Step-by-step explanation:
Beta-lactam antibiotics are specifically designed to interfere with the synthesis of peptidoglycan, which is a crucial component of bacterial cell walls. This complex molecule composed of polysaccharide chains cross-linked by peptides is vital for the bacteria's protection. Therefore, the bacterial structure most likely targeted by these drugs is c) Cell Wall.
The mechanism of these antibiotics involves mimicking D-amino acids to disrupt the cell wall development. For example, penicillins, which are a group of beta-lactam antibiotics, inhibit the transpeptidase cross-linking activity of penicillin-binding proteins, essential for cell wall synthesis.
As human cells do not possess peptidoglycan, targeting this process exhibits selective toxicity and is particularly effective against bacteria, making these antibiotics bactericidal.