Humoral Response

• Where do B-lymphocytes remain until maturity?

  Bone marrow
• What happens to B-lymphocytes after they mature?

  They spread through the body
• What are the receptors on the surface of B cells sometimes referred to as?

  Antibody receptors
• What part of each antibody molecule forms a glycoprotein receptor?

  A small part of the antibody molecule
• What do genetically identical B cells with the same BCRs form?

  A clone
• What do mature B cells have on their cell surface membranes?

  Many different types of antibody receptor
• What is required for B cells to play their role in the immune response?

  They need to be activated and increase in number
• What is the first step in the activation of B cells?

  Clonal selection
• What do B cells bind to during clonal selection?


  Antigens on antigen presenting cells or pathogens
• What types of cells can be antigen presenting cells?

  Phagocytes, infected cells, or pathogens
• What activates B cells during clonal selection?

  Binding to antigens and interleukins from T helper cells
• What occurs during clonal expansion of B cells?

  Activated B cells divide by mitosis
• What do activated B cells produce through division?

  Clones of identical B-lymphocytes
• What do some B-lymphocytes differentiate into after activation?

  Plasma cells
• What do plasma cells secrete into the blood?

  Lots of antibody molecules
• Where can antibodies secreted by plasma cells be found?

  In blood, lymph, or linings of lungs and gut
• What do the other B-lymphocytes become after activation?

  Memory cells
• How long do memory cells remain in circulation?

  A long time
• Process of Humoral Response

  • B Cell antibodies bind with complementary antigen
  • B cell engulfs pathogens & present the antigens on the cell surface to become (antigen-presenting cell, APC)
  • T helper cells bind to antigens on APC, activating the B cell
  • B cell divides by mitosis to form plasma & memory cells
• What do plasma cells do?

  Secrete antibodies specific to the antigen on the APC, which destroy any pathogens
• What do memory cells do?

  Circulate in the blood, ready to divide upon reinfection