BIOM 250 1st Edition Exam # 3 Study GuideDescribe the two types of immunity.Answer: Adaptive immunity has a specific defense against a specific target. Innate immunity consists of general defenses against any pathogenWhat are the two components of adaptive immunity?Answer: The two components of adaptive immunity are humoral and cellular immunity. Humoral immunity is based on the production of antibodies against antigens and cellular immunity is based on the actions of T lymphocytes.Define an antigen.Answer: A substance that can induce an immune response. The antigen either binds to an immune cell receptor or causes immune cells to produce an antibody. Most antigens are proteins, but some are large polysaccharides. What is an epitope?Answer: Small region of an antigen that is recognized by an antibody or cell receptor.Describe the structure of an antibody.Answer: A simple bivalent antibody has two binding sites, is composed of 2 heavy chains and 2 light chains, and is shaped like a Y. One end of each chain has a variable region designed to bind only one antigen. The other chain ends are the constant regions, and are identical for each TYPEof antibody.How many variable regions are on each antibody?Answer: There are two variable regions on each antibody, therefore—each antibody can bind to two antigens.What is the function of the constant regions of an antibody?Answer: After binding to an antigen via the variable region, the exposed constant region is then able to bind to complements to attack the pathogen or bind to other immune cell receptors andactivate the immune cell.What are the three immunoglobulin classes and describe their defining properties.Answer: 1) IgG: monomer that takes up about 80% of the total antibodies of the blood; is able to easily cross from the bloodstream to the tissues; can activate complements; long-lived in the bloodstream; can cross placenta and confers passive immunity to infant2) IgM: pentamer that takes up about 5-10% of total antibodies of the blood; 5 joined monomers gives you 10 binding sites; multiple sites causes clumping of cells/viruses; large size prevents IgM from crossing barriers like IgG does3) IgA: dimer when it is ready for secretion; 10-15% of total antibodies in the blood; 2 monomers linked by a polypeptide—secretory component; can enter and pass through a mucosal cell; important component for mucus; binds to pathogens and prevents attachment of the pathogen to mucosal surface; What cells are responsible for making antibodies?Answer: B cells. Each specific type of B cell makes on specific antibody. (true/false) All nucleated cells display MHC on their surface. Answer: True. Even non-immune cells display part of one of their own proteins or if the cell is infected then pathogen proteins will be displayed by the MHC. What are the two types of cells that activated B cells differentiate into?Answer: Once the B cell has been activated, the cell multiplies and some cells differentiate into antibody-producing plasma while others differentiate into memory cells.What is the strength of the bond between epitope and antibody dependent on?Answer: The strength of the bond in dependent on the affinity—some antibodies bind strongly while some are weaker.Identify and describe the 4 processes an antibody does to a pathogen.Answer: 1) Agglutination: ability of an antibody to cause clumping of bacteria, virus and toxins2) Opsonization: coating of pathogen with antibodies—this enhances phagocytosis and helps cytotoxic cells recognize and attack pathogens3) Activation of complement: antibody attracts complement and induces lysis4) Neutralization: coating of structures on bacteria which inhibits adherence; coating of toxins and prevents them from getting to target or attacking