What is the main function of antibodies in the immune system?

Antibodies play a crucial role in the immune system by identifying and neutralizing foreign objects, such as bacteria and viruses. They are a type of protein produced by B cells, which are a form of white blood cell. When an infection occurs, these antibodies attach to antigens on the surface of pathogens, marking them for destruction. This process can neutralize the effects of toxins produced by bacteria or prevent viruses from entering and infecting cells.

Furthermore, antibodies can also activate other components of the immune system, such as complement proteins, that contribute to the destruction of pathogens. This specificity and adaptability make antibodies essential for the immune response, helping the body to recognize and remember pathogens for quicker responses in future exposures.

The other options do not relate to the function of antibodies. Energy production, food digestion, and cellular respiration are processes managed by various body systems and cellular mechanisms, but they are not functions of antibodies in the immune defense.