Which lymphocyte is responsible for producing and secreting antibodies?

Which lymphocyte is responsible for producing and secreting antibodies?

• A. Memory B-lymphocyte
• B. Natural killer cell
• C. Memory T-lymphocyte
• D. Plasma cell

Answer: (D)

The correct choice is the plasma cell. Plasma cells are a type of B lymphocyte that has differentiated after encountering an antigen. Their primary function is to produce and secrete antibodies, which are proteins that specifically target and neutralize pathogens such as bacteria and viruses. When B cells are activated by an antigen, they proliferate and can either form memory B cells, which provide long-lasting immunity, or differentiate into plasma cells, which are the effector cells that generate large quantities of antibodies. In contrast, memory B-lymphocytes are important for long-term immunity but do not actively produce antibodies until re-exposed to the antigen. Natural killer cells play a role in the innate immune response and are responsible for identifying and destroying infected or cancerous cells, rather than producing antibodies. Memory T-lymphocytes are involved in the adaptive immune response, recognizing specific antigens and orchestrating a response, but do not secrete antibodies. Thus, the role of antibody production is specifically attributed to plasma cells.

The correct choice is the plasma cell. Plasma cells are a type of B lymphocyte that has differentiated after encountering an antigen. Their primary function is to produce and secrete antibodies, which are proteins that specifically target and neutralize pathogens such as bacteria and viruses. When B cells are activated by an antigen, they proliferate and can either form memory B cells, which provide long-lasting immunity, or differentiate into plasma cells, which are the effector cells that generate large quantities of antibodies.

In contrast, memory B-lymphocytes are important for long-term immunity but do not actively produce antibodies until re-exposed to the antigen. Natural killer cells play a role in the innate immune response and are responsible for identifying and destroying infected or cancerous cells, rather than producing antibodies. Memory T-lymphocytes are involved in the adaptive immune response, recognizing specific antigens and orchestrating a response, but do not secrete antibodies. Thus, the role of antibody production is specifically attributed to plasma cells.