Unit 2 - Specific Defences Flashcards
What are antigens
Substances that provoked a specific response
What Do the specific defenses of the immune system do
Recognizes foreign substances is not belonging to the body develops a specific immune response against them
What are anti-bodies
Proteins produced by the body in response to an antigen
What is acquired immunity
Protection and animal develops again certain types of microbes or foreign substances. Developed during an individual’s life time. Can be acquired actively or passively
What is active immunity
Immune system response following exposition to microorganisms or foreign substances
What is passive immunity
Antibodies are preformed by some other animal. Lasts only as long as the antibodies are present which is weeks to months
What is humoral immunity. Antibody mediated
Production of antibodies against foreign organisms and substances.
Where are anti-bodies found
In extracellular fluid’s such as blood plasma, lymphatic fluid, mucus secretions
Which cells are responsible for production of antibodies
The B lymphocytes
What does a Humoral immunity protect against
Bacteria, bacterial toxins and viruses
What is cell mediated immunity
Involve specialized T cells that acts against foreign organisms or tissues. Regulate the activation and proliferation of other immune system cells like macrophages
What is cell mediated immunity the most effective against
Bacteria and viruses within phagocytic or infected host cells, fungi, protozoa, Helminthes.
What is cell mediated immunity important for
Primary responder to transplanted tissue an important defense against cancer
What are antigens
Substance that the body recognizes as being foreign against which enemy in response will be mounted. Most are proteins are large polysaccharides. Lipids nucleic acid’s are usually only anti-genic if combined with proteins are polysaccharides.
What are non-microbial agents that have antigens
Pollen, egg white, blood cell surface molecules, serum proteins from other individuals
What are antigenic determinant’s or epitopes
Specific region on the surface of an antigen against which anti-bodies are formed. An antigen usually has several antigenic determinant sites that cause the production of different anti-bodies
What is a Hapten
Substance of low molecule wait that does not cause the formation of antibodies by itself but does when combined with the carrier molecule
What are antibodies
Highly specific proteins that are made in response to an antigen. Recognize unbind antigens. Hope to neutralize or destroy antigens
Describe the structure of an anti-body
Each anybody has at least two identical binding sites that bind antigenic determinant.
What is a valance
Number of antigen binding sites. Most anti-bodies are bivalent and are monomers
Describe the shape of an antibody monomer
It is a Y shape with 2 antigen binding sites
What does the variable region of the antibody monomer do
Has 2 binding sites that are antigen specific.
What are the constant regions for
For the 5 classes of immunoglobulins
What is the FC region of the antibody monomer
Fragment that crystallized in cold storage. If exposed after both arms Jim binding sites attached to an antigen the FC regions of adjacent antibodies combined complement and destroy the pathogen. Can bind to a cell and leave the antigen binding sites of adjacent antibodies free to react with antigens.
Describe the immunoglobulin classes
Five classes, determined by the constant regions. Each class please a different role in the immune response.
Describe immunoglobulin G
Bivalent monomer. Accounts for 80% of all antibodies in zero. Readily crosses walls of blood vessels and enters tissue fluids. Protect against circulating bacteria and viruses, neutralize bacterial toxins, trigger complement system, enhances phagocytosis when bound to an antigen. Maternal IgG can cross the placenta and confirm passive immunity to a fetus also present in the colostrum. 
Describe immunoglobulin M
It is a pentamer. 5 to 10% of antibodies in serum. It’s large-size prevents RGM from moving freely and it generally remains in blood vessels. First antibodies to appear in response to initial exposure to an antigen in and relatively short-lived, a second exposure results mostly in increased IgG production. Valuable in the diagnosis of the disease since it is first to appear in primary infection and is very short-lived. Effective in aggregating antigens and then reactions were involving complement. Can enhance ingestion of target cells by phagocytic cells
Describe immunoglobulin a
10 to 15% of antibodies in serum, but common in most mucous membranes and body secretions. Most abundant immunoglobulin in the body. Has two Forms
What are the two forms of immunoglobulin a
Serum IGA, secretory IGA