FREE LST Antigen Questions and Answers
What is clonal expansion in the context of lymphocyte activation?
Clonal expansion is the process by which lymphocytes that have recognized a specific antigen rapidly proliferate to mount an effective immune response.
What is the role of T cell receptors (TCRs) in antigen recognition?
T cell receptors (TCRs) on T cells recognize and bind to antigens presented by MHC molecules on the surface of antigen-presenting cells.
What is the primary function of lymphocytes in the immune system?
Lymphocytes are a type of white blood cell that plays a critical role in the immune response by fighting infections and providing immunity.
What molecule on the surface of B cells is responsible for antigen recognition?
The B cell receptor (BCR) on the surface of B cells binds to specific antigens, initiating the immune response.
How do cytotoxic T cells kill infected cells?
Cytotoxic T cells kill infected cells by secreting perforin and granzymes, which induce apoptosis in the target cells.
Which type of MHC molecule presents endogenous antigens to CD8+ T cells?
MHC class I molecules present endogenous antigens (from within the cell) to CD8+ cytotoxic T cells.
What type of antigens do MHC class II molecules present?
MHC class II molecules present exogenous antigens (from outside the cell) to CD4+ helper T cells.
What is the initial event in the lymphocyte activation process?
The initial event in lymphocyte activation is the recognition of an antigen by a specific receptor on the lymphocyte.
Which cells are considered professional antigen-presenting cells (APCs)?
Dendritic cells, macrophages, and B cells are professional antigen-presenting cells that process and present antigens to T cells.
What are the main types of lymphocytes involved in antigen recognition?
T cells and B cells are the primary lymphocytes involved in antigen recognition and immune response.
What cytokine is essential for the proliferation of activated T cells?
Interleukin-2 (IL-2) is a cytokine that is crucial for the proliferation and survival of activated T cells.