1 What is the mechanism of action of interferon Alert neighboring cells and protect them from becoming infected Bind to surface receptors on those cells and activate second messenger systems within This induces synthesis of dozens of antiviral proteins that defend a cell by such means as breaking down viral genes or preventing viral replication Also activate NK cells and macrophages which destroy infected cells before they can liberate a swarm of newly replicated viruses Also confer resistance to cancer 2 When are complement proteins produced When do they become active Activated in the presence of pathogens 3 When do neutrophils become phagocytic As they encounter bacteria 4 What cells attack virus infected cells and cancer cells Lymphocytes 5 What is the purpose of fever inhibits reproduction of bacteria and viruses 6 What are the non specific defense mechanisms prior exposure Present from birth 7 How are neutrophils attracted to inflamed sites Promotes interferon activity elevates metabolic rate and accelerates tissue repair and Guard against a broad range of pathogens and their effectiveness does not depend on Chemical messengers released by basophils mast cells blood plasma and damaged tissue These inflammatory chemicals stimulate Leukocyte margination adhesion to capillary walls Diapedesis crawling through capillary walls Chemotaxis movement toward source of inflammatory chemicals Phagocytosis engulfing bacteria and other pathogens 8 Which body system carries out immune responses Lymphatic system 9 What are the functions of helper T cells Suppressor T cells Cytotoxic T cells NK cells Helper T cells Promote the action of cytotoxic cells as well as key in humoral immunity and nonspecific resistance Only T cell no involved in cellular immunity only Suppressor Regulatory T cells limit the immune response by inhibiting multiplication and cytokine secretion by other T cells Seem important in preventing autoimmune diseases Cytotoxic T cells Carry out attack on foreign cells The effectors of cellular immunity NK cells Attack and destroy bacteria transplanted tissues and host cells cells of one s own body that have either become infected with viruses or turned cancerous Responsible for a mode of defense called immune surveillance patrol body for pathogens and diseased host cells 10 What do helper T cells do during recognition in humeral immunity Binds to Ag MHCP and secretes interleukins to activate the B cell triggering clonal selection 11 What activates an immune response Antigens pathogens entering the body Region of antigen called epitope stimulates 12 What is the term for the first encounter between an immunocompetent lymphocyte and an immune response invading antigen Antigen Challenge 13 What is the difference between a complete antigen and hapten Complete antigen any molecule that triggers an immune response Haptens are too small to be antigenic themselves can stimulate immune response by binding to a host macromolecule and creating a unique complex that the body recognizes as foreign 14 Which Ig crosses the placenta 15 Which Ig is a potent agglutinator IgG IgM IgE IgA Alveoli Air Pressure Inspiration 16 Which Ig is primarily involved in allergic reactions 17 Which Ig is found in body secretions 18 Actual site of gas exchange in the lungs is the 19 The movement of air in and out of the lungs is due to Lungs expand increasing space inside Less air particles per square inch in the lung smaller concentration than outside so air moves into the lungs by diffusion Expiration Lungs contract increasing air pressure More particles per square inch more squashed together than outside so air moves out of the lungs by diffusion 20 How does the pleura and pleural fluid create a pressure gradient and reduce friction Reduces friction by acting as lubricant that enables lungs to expand and contract with minimal friction Creates pressure gradiant by 21 What changes occur as the bronchial tree becomes smaller Walls lose cartilaginous support 22 What will a pneumothorax result in The presence of air in the pleural cavity Visceral and parietal pleurae separate No negative intrapleural pressure lungs recoil and collapse atelectasis 23 Define the respiratory membrane Barrier between alveolar air and blood Brainstem Respiratory Centers Automatic unconscious cycle of breathing is controlled by three pairs of respiratory centers in the reticular formation of the medulla oblongata and the pons Respiratory nuclei in medulla o Ventral respiratory group VRG Primary generator of the respiratory rhythm Inspiratory neurons in quiet breathing eupnea fire for about 2 seconds Expiratory neurons in eupnea fire for about 3 seconds allowing inspiratory muscles to relax Produces a respiratory rhythm of 12 breaths per minute o Dorsal respiratory group DRG Modifies the rate and depth of breathing Receives influences from external sources o Pons Pontine RG Modifies rhythm of the VRG by outputs to both the VRG and DRG Adapts breathing to special circumstances such as sleep exercise vocalization and emotional responses