BI 122 IMMUNITY Terms in this set (21) The lympatic system splits into what two parts? Non-specific and specific First line of defense non-specific physical barriers, chemical barriers, microbial antagonism second line of defense Fever, inflammation,

BI 122 IMMUNITY Terms in this set (21) The lympatic system splits into what two parts? Non-specific and specific First line of defense non-specific physical barriers, chemical barriers, microbial antagonism second line of defense Fever, inflammation, phagocytosis, interferons, complement Antibody-mediated (Humoral) immunity primarly involves B-cells targets extracellular microbes cell-mediated immunity involves T-cells, targets intracellular microbes Nonspecific defense fucntion the same way regardless of the pathogen or the number of exposures " one pony" Non specific to anything. Target can be anything Physical barriers Skin- keratinized cells, sloughing of skin cells, Mucous membranes- mucus- traps particles Cilia- sweep microbes away hairs- trap microbes Chemical barriers sebum- fatty acids are antimicrobial- kill bacteria sweat- salt can be antimicrobial Gastric acid- few organisms can survive PH 2 lysozyme- host enzymem that cleaves peptidoglycan; present in tears, sweat, mucus, and saliva Peptidolycan a structure found in the cell wall of eubacteria (gram positive) that are not found in mammalian cells Microbial antagonism ability of teh host's normal flora to prevent pathogens from colonzing. Comepte for space, nutrients, and produce antibacterial factors. Fever a systemic increase in body temp. Benefits: slows down growth of pathogens speeds up host defense and inflammation makes host feel "ill" - more likely to rest and recover Inflammatoin A tissue repsonse to injury that helps prevent the spread of infection agents into nearby tissues. begins within minutes; occurs within our hour. BI 122 IMMUNITY Major events in acute inflammation Vasodilation increased permability of capillaries leukocytes accumulate at site of injury. Charateristic s/sx of inflammation Redness,- increased blood flow to area, heat- from warmth of blood swelling- accumulation of fluid pain - from innjury to local nerves. Phagocytosis Neutrophils and marcophages engulf foregin particles and cells. Fever- increases phagocytic activity TWO main phagocytic cells Neturophils, marcophages Neutrophils leave circulation and mirgrate to site of inflammation/infections 1st responders in inflammation Macrophages Develop from monocytes that circulate in the bloodstream - are fixed or wandering in tissues - Late responders in infammation- Last longest. Interferon is a protein produced by virus-infection host cells. interferon binds to the receptors of non-infected host cells. Complement system a group of plasma proteins, they interact with each other in a step- wise manner. benefits of complement 1.) initiation and amplification of inflammation 2.) attracts phagocytes: acts as a chemical singal 3.) Lyse bacteria & foregin cells via membrane attack complexes 4.) enhances phagocytosis through opsonization (Handles like corn on the cob).