The primary structural component of the bacterial cell wall is peptidoglycan. This polymer consists of sugars and amino acids, providing structural support and rigidity to the cell. In bacteria, it forms a protective layer that helps maintain shape and withstand external pressure. The thickness and composition of peptidoglycan can vary, contributing to the classification of bacteria as Gram-positive or Gram-negative, both of which influence their response to antibiotics and susceptibility to environmental factors.