What is the primary role of the capsule in bacterial cells?

The primary role of the capsule in bacterial cells is to provide protection against phagocytosis and dehydration. The capsule is a gelatinous layer that surrounds some bacterial cells, and it serves several important functions that contribute to the survival and virulence of the bacteria.

By providing a physical barrier, the capsule helps prevent the engulfment of bacterial cells by immune cells, such as macrophages, through a process called phagocytosis. This allows the bacteria to evade the host's immune response and persist in hostile environments. Additionally, the capsule aids in preventing dehydration by retaining moisture around the bacterial cell, thus allowing it to survive in dry conditions.

While options like enabling photosynthesis, storing nutrients, and assisting with cell respiration have their roles in different cellular contexts, they do not accurately represent the primary function of the capsule in bacteria. The capsule is primarily recognized for its defensive and protective capabilities, making it a significant feature in the biology of many pathogenic bacteria.