Humoral immunity

• What is the humoral response?

  The immune response involving B cells and antibodies
• What type of white blood cells are involved in the humoral response?

  B-lymphocytes
• Where do B-lymphocytes come from?

  Bone marrow
• How do B-lymphocytes target pathogens?

  By producing antibodies
• What is the main function of antibodies in the immune response?

  To neutralize or destroy pathogens
• What is the difference between cell-mediated and humoral responses?

  Cell-mediated involves T cells, humoral involves antibodies
• Where can B cell receptors bind to foreign antigens?

  On pathogens or antigen-presenting cells (APCs) (clonal selection)
• What binds to the B cell to activate it?

  T helper cells
• What happens after a B cell is activated?

  It divides by mitosis to form plasma cells and memory cells (clonal expansion)
• What do plasma cells produce?

  Antibodies that are complementary to the antigen
• What type of immune response involves plasma cells producing antibodies?

  Primary immune response
• What is the role of memory cells?

  They stay in the bloodstream to provide long-term immunity by recording the antibodies that bind to that pathogen in case of a second infection
• What happens if memory cells encounter the same antigen again?

  They divide to form plasma cells to produce large numbers of antibodies and more memory cells
• What happens during the primary immune response?

  A small number of B cells produce antibodies, which last a few days
• What is the main difference between the primary and secondary immune response?

  Secondary response is faster and produces more antibodies
• Why is the primary response slower?

  There is a delay while B cells are activated by T helper cells and there are fewer initial B cells to produce antibodies
• What happens to the production of antibodies in the secondary response?

  Antibodies are produced more quickly and in larger quantities
• How does the secondary response contribute to long-term immunity?

  It produces more memory cells that provide long-term immunity
• What is the benefit of having memory cells after an infection?

  Memory cells allow a quicker and stronger response to the same antigen
• What provides long-term protection against reinfection?

  Memory cells in the bloodstream
• Where does the humoral immune response occur?

  In the blood and tissue fluid
• What type of lymphocytes does the humoral response involve?

  B-lymphocytes
• Where do B-lymphocytes mature?

  Bone marrow
• What is the role of B-lymphocytes in the humoral immune response?

  They produce antibodies against pathogens
• What happens when a pathogen enters the blood or tissue?

  A B-lymphocyte with a complementary receptor binds
• How does a B cell take in an antigen?

  By endocytosis
• What does a B cell do after binding to an antigen?

  It displays the antigen on its surface
• What does APC stand for in the context of B cells?

  Antigen-Presenting Cell
• What occurs when a T-helper cell binds to the presented antigen?

  It activates the B cell
• What process allows the activated B cell to produce many identical cells?

  Mitosis which produces lots of identical cells (clonal selection)
• What are the two types of cells that B cells develop into after activation?

  • Plasma cells: Produce antibodies against pathogens
  • Memory cells: Survive for decades and respond quickly to reinfection
• What do plasma cells produce?

  Antibodies complementary to the pathogen
• How do memory cells function in the immune response?

  They respond quickly if the pathogen invades again
• How long can memory cells survive in the bloodstream?

  For decades