Final answer:
Specialized white blood cells called B cells are responsible for producing antibodies that bind with and neutralize antigens entering the body. These antibodies signal for the destruction of the pathogens by other immune cells.
Step-by-step explanation:
When an antigen enters the body, specialized white blood cells called B cells produce antibodies, which in turn combine with the antigens to neutralize them. B cells, or B lymphocytes, are a crucial part of the adaptive immune system, which is the specific defense mechanism against pathogens like viruses and bacteria. B cells function by recognizing antigens through their surface receptors and, upon activation, differentiate into plasma cells. These plasma cells secrete antibodies, which are Y-shaped proteins that can bind specifically to the antigens, marking them for destruction by other immune cells such as phagocytes.
The immune system is a complex network where not only B cells but other types of cells like T cells and antigen-presenting cells, such as macrophages, play pivotal roles. T cells, for example, are necessary for both helping to activate B cells and also for directly attacking infected cells in what's known as the cell-mediated immune response. Together, B and T cells ensure a robust and specific response to invading pathogens, which includes the production of antibodies and the destruction of infected cells.