THE IMMUNE SYSTEM FINAL PAPER 2026
SOLVED QUESTIONS AND ACCURATE
ANSWERS GRADED A+
● acquired immunity. Answer: The kind of defense that is mediated by
B lymphocytes (B cells) and T lymphocytes (T cells). It exhibits
specificity, memory, and self-nonself recognition. Also called adaptive
immunity.
● active immunity. Answer: Long-lasting immunity conferred by the
action of a person's B cells and T cells and the resulting B and T memory
cells specific for a pathogn. Active immunity can develop as a result of
natural infection or immunization.
● AIDS (acquired immunodeficiency syndrome). Answer: The name of
the late stages of HIV infection, defined by a specified reduction of T
cells and the appearance of characteristic secondary infections.
● anaphylactic shock. Answer: An acute, whole-body, life-threatening,
allergic response.
● antibody. Answer: A protein secreted by plasma cells (differentiated B
cells) that binds to a particular antigen and marks it for elimination; also
called immunoglobulin. All antibody molecules have the same Y-shaped
, structure and in their monomer form consist of two identical heavy
chains and two identical light chains joined by disulfide bridges.
● antigen. Answer: A macromolecule that elicits an immune response
by lymphocytes.
● antigen presentation. Answer: The process by which an MHC
molecule binds to a fragment of an intracellular protein antigen and
carries it to the cell surface, where it is displayed and can be recognized
by a T cell.
● antigen receptor. Answer: The general term for a surface protein,
located on B cells and T cells, that binds to antigens, initiating acquired
immune responses. The antigen receptors on B cells are called B cell
receptors (or membrane immunoglobulins), and the antigen receptors on
T cells are called T cell receptors.
● antigen-presenting cell. Answer: A cell that ingests bacteria and
viruses and destroys them, generating peptide fragments that are bound
by class II MHC molecules and subsequently displayed on the cell
surface to helper T cells. Macrophages, dendritic cells, and B cells are
the primary antigen-presenting cells.
● apoptosis. Answer: The changes that occur within a cell as it
undergoes programmed cell death, which is brought about by signals
SOLVED QUESTIONS AND ACCURATE
ANSWERS GRADED A+
● acquired immunity. Answer: The kind of defense that is mediated by
B lymphocytes (B cells) and T lymphocytes (T cells). It exhibits
specificity, memory, and self-nonself recognition. Also called adaptive
immunity.
● active immunity. Answer: Long-lasting immunity conferred by the
action of a person's B cells and T cells and the resulting B and T memory
cells specific for a pathogn. Active immunity can develop as a result of
natural infection or immunization.
● AIDS (acquired immunodeficiency syndrome). Answer: The name of
the late stages of HIV infection, defined by a specified reduction of T
cells and the appearance of characteristic secondary infections.
● anaphylactic shock. Answer: An acute, whole-body, life-threatening,
allergic response.
● antibody. Answer: A protein secreted by plasma cells (differentiated B
cells) that binds to a particular antigen and marks it for elimination; also
called immunoglobulin. All antibody molecules have the same Y-shaped
, structure and in their monomer form consist of two identical heavy
chains and two identical light chains joined by disulfide bridges.
● antigen. Answer: A macromolecule that elicits an immune response
by lymphocytes.
● antigen presentation. Answer: The process by which an MHC
molecule binds to a fragment of an intracellular protein antigen and
carries it to the cell surface, where it is displayed and can be recognized
by a T cell.
● antigen receptor. Answer: The general term for a surface protein,
located on B cells and T cells, that binds to antigens, initiating acquired
immune responses. The antigen receptors on B cells are called B cell
receptors (or membrane immunoglobulins), and the antigen receptors on
T cells are called T cell receptors.
● antigen-presenting cell. Answer: A cell that ingests bacteria and
viruses and destroys them, generating peptide fragments that are bound
by class II MHC molecules and subsequently displayed on the cell
surface to helper T cells. Macrophages, dendritic cells, and B cells are
the primary antigen-presenting cells.
● apoptosis. Answer: The changes that occur within a cell as it
undergoes programmed cell death, which is brought about by signals
