Plasma cells and what do they secrete?

• A. Enzymes
• B. Antibodies
• C. Hormones
• D. Cytokines

Answer: (B)

Plasma cells are specialized B cells that actively produce and secrete antibodies (immunoglobulins). After encountering an antigen and receiving help from T cells, B cells differentiate into plasma cells that churn out large amounts of a single antibody type. These antibodies travel through body fluids to bind their specific antigens on pathogens or toxins, neutralizing them and helping other parts of the immune system clear infections. Enzymes are proteins that catalyze chemical reactions, hormones are endocrine signals traveling through the bloodstream to distant targets, and cytokines are signaling molecules coordinating immune responses. The defining product of plasma cells is antibodies, making them the best answer.