This system distinguishes self from nonself and defends the body against pathogens and cancer cells.
What is the immune system?
These barriers are the first line of defense and hinder pathogen penetration.
What are physical barriers?
These two major lymphocyte types carry out acquired immunity.
What are T cells and B cells?
These Y-shaped glycoproteins have two heavy chains and two light chains
What are antibodies?
T cells that recognize self-antigens with low affinity undergo this process.
What is positive selection?
These drugs suppress the immune system and made organ transplantation possible.
What are immunosuppressants?
These cells are the first to encounter viruses or bacteria and present antigens to T cells.
What are dendritic cells?
These T cells directly destroy infected host cells.
What are killer T cells (cytotoxic T cells)?
These regions on antigens are where antibodies bind.
What are epitopes?
DP cells that fail to recognize anything die by this process.
What is death by neglect?
This biological preparation contains a weakened or killed agent to stimulate antibody production.
What is a vaccine?
These lymphocytes kill infected or cancerous cells and help determine whether to activate acquired immunity.
What are natural killer (NK) cells?
This process ensures only cells responsive to a specific antigen multiply.
What is clonal selection?
Each antibody can bind this many antigens.
What is two?
Recognition of self-antigens with high affinity triggers this programmed cell death pathway.
What is apoptosis?
These white blood cells arise from bone marrow stem cells and circulate through blood and lymph.
What are leukocytes?
These cells engulf invaders via endocytosis before traveling to the spleen to activate helper T cells.
What are dendritic cells?
These T cells release interleukins to stimulate maturation of B cells.
What are helper T cells (CD4+)?
These antibodies come from the progeny of a single B cell and bind only one antigen.
What are monoclonal antibodies?
These proteins on cells help the immune system distinguish self from nonself.
What are MHC proteins?
This family of proteins, including IL‑2 and IL‑7, regulates survival and proliferation of T cells.
What are interleukins?
These innate immune cells secrete cytokines that recruit other immune cells and collaborate with dendritic cells.
What are NK cells?
This type of immune memory cell persists after infection and ensures faster responses later.
What are memory T cells?
Antibody genes are inherited as these small DNA segments that assemble in developing B cells.
What are gene fragments (VDJ fragments)?
Breakdowns in immune recognition can result in this class of disease where the body attacks itself.
What are autoimmune diseases?