Phagocytosis: A type of endocytosis in which large particulate substances are taken up by a cell. It is carried out by some protests and by certain immune cells of animals.
Lysozyme: An enzyme that destroys bacterial cell walls; in mammals, fount in sweat, tears, and saliva.
Neutrophil: The most abundant type of white blood cell. Neutrophils are phagocytic and tend to self-destruct as they destroy foreign invaders, limiting their life span to a few days.
Interferons: A protein that has antiviral or immune regulatory functions. Interferon alpha and interferon beta, secreted by virus-infected cells, help nearby cells resist viral infection; interferon-y, secreted by T cells, helps activate macrophages.
Histamine: A substance released by mast cells that causes blood vessels to dilate and become more permeable inflammatory and allergic responses.
Natural Killer (NK) Cell: A type of white blood cell that can kill tumor cells and virus-infected cells as part of innate immunity.
Epitope: A small accessible region of an antigen to which an antigen receptor or antibody binds; also called an antigenic determinant.
Antigen: A macromolecule that elicits an immune response by binding to receptors of B cells or T cells.
Effector Cell: A lymphocyte that has undergone clonal selection and is capable of mediating an acquired immune responses.
Memory Cell: One of a clone of long-lived lymphocytes, formed during the primary immune responses, that remains in a lymphoid organ until activated by exposure to the same antigen that triggered its formation. Activated memory cells mount the secondary immune response.
Clonal Selection: The process by which an antigen selectively binds to and activates only those lymphocytes bearing receptors specific for the antigen. The selected lymphocytes proliferate and differentiate into a clone of effector cells and a clone of memory cell specific for type stimulating antigen.
Helper T Cell: A type of T cell that, when activated, secretes cytokines that promote the response of B cells (humoral response) and a cytotoxic T cells (cell-mediated response) to antigens.
Immunization: Generating a state of immunity by artificial means. In active immunization, vaccination, a weakened form is administered. In passive, Antibodies specific for a particular microbe are administered temperorary protection.
Humoral Immunity: The branch of acquired immunity that involves the activation of B cells and that leads to the production of antibodies which defend against bacteria and viruses in body fluids.
Cell Mediated Immunity: The branch of acquired immunity that involves the activation of cytoxic T cells, which defend against infected cells.
Monoclonal Antibodies: Any of a preparation of antibodies that have been produced by a single clone of cultured cells and thus are all specific for the same epitope.
Agglutination: The clumping of cells (bacteria, red) in the presence of an antibody. Creates a large complex and prevents foreign material from entering.
Anaphylactic Shock: Occurs when an allergic response triggers a quick release from mast cells of large quantities of immunological mediators (histamines, prostaglandins, leukotrienes) leading to a drop in blood pressure and difficulty breathing.
Basophils: A type of white blood cell in the circulation IEG surface, release chemical mediators causing IEG to bind to a specific allergen.
Multiple Choice Questions
1. Which cells and which signaling molecules are responsible for initiating an inflammatory response?
A. phagocytes: chemokines
C. mast cells:histimines
D. dendritic cells:interferons
2. Memory Cellls
A. Produce cyclosporine
B. Are responsible for passive immunity
C. prevent an animal from encountering certain antigens
D. provide an accelerated immune response upon second exposure to a particular antigen
E. All of the above
3. The inflammatory response includes all of the following except
A. vessel constriction
B. temperature increase
C. increased blood flow
D. phagocyte attack
E. all of the above
Answers: 1. c 2. d 3. a
Things Due Tomorrow
Chi Square Analysis
Ch. 43 Vocab
Ch. 43 Vocab Quiz