[Campbell Biology P.1014] Based on the information presented in Figure 43.19 and your underst... | Practice Question

Based on the information presented in Figure 43.19 and your understanding of adaptive immunity, what is the primary function of the cell-surface antigen receptors on memory B cells?

  • A: To present processed antigen fragments to cytotoxic T cells for direct pathogen killing.
  • B: To facilitate rapid recognition and activation upon re-exposure to the same specific antigen, leading to a faster and stronger secondary immune response.
  • C: To secrete large quantities of antibodies immediately upon their formation from plasma cells.
  • D: To directly phagocytose and degrade pathogens more efficiently than antigen-presenting cells.

Explanation

The question mark in Figure 43.19 prompts consideration of memory B cell function. Memory B cells, formed during the primary response, retain specific antigen receptors on their surface. This allows them to quickly recognize the same antigen upon subsequent exposure. Their rapid activation, proliferation, and differentiation into plasma cells and more memory B cells lead to a faster, stronger, and more prolonged secondary immune response compared to the primary response.