Immunology

    Cards (49)

    • natural barriers to infection
      • skin
      • skin flora
      • blood clotting
      • inflammation
      • phagocytosis
      • mucous membranes
      • stomach acid
      • lysozyme
    • skin barrier to infection - forms a tough barrier of collagen to prevent entry of pathogens, maintained by vitamin C
    • skin flora competes with pathogenic bacteria to prevent growth (the gut also has a flora)
    • blood clotting seals wounds to prevent entry of pathogens
    • inflammation - cells surround the site of infection to prevent the spread of disease
    • phagocytosis - invading microbes are engulfed and destroyed
    • mucous membranes - mucus and ciliated cells trap microbes and help to remove them
    • stomach acid - kills bacteria
    • lysozyme - in tears and saliva, hydrolyses the peptidoglycan in bacterial cell walls
    • signs of inflammation
      • redness
      • swelling
      • heat
      • pain
    • functions of inflammation
      • increases blood flow to the area
      • destroys the cause of infection
      • repairs / replaces damaged tissue
    • phagocytosis
      • pathogens entering the body are surrounded by pseudopodia
      • pathogens are engulfed (phagocytosed) by endocytosis (ATP)
      • a vacuole forms enclosing the bacteria
      • lysosomes fuse with the vacuole
      • toxic compounds (lysosomal enzymes and hydrogen peroxide) destroy the ingested pathogens
      • the debris from pathogen is released by exocytosis
      • antigens from the pathogens are presented on the surface of the macrophage
      • the antigens now stimulate lymphocytes
    • natural barriers to infection are known as non-specific immunity
    • pathogenic - an organism that causes damage to its host
    • infectious - a disease that may be transmitted from one individual to another
    • carrier - an infected person or other organism that shows no symptoms when infected but can transmit the disease onto another
    • disease reservoir - a long-term host of a pathogen ; this may be in human or another animal and may be a source of infection or disease outbreak
    • endemic - a disease occurring frequently, at a predictable rate, in a specific location or population
    • epidemic - the rapid spread of infectious disease to a large number of people in a short period of time
    • pandemic - an epidemic over a very wide area, crossing international boundaries and affecting a large number of people
    • infection - a transmissible disease often acquired by inhalation, ingestion or physical contact
    • vaccine - a weakened or inactive pathogen or toxin or antigen that stimulates the immune system to produce an immune response against it without causing infection
    • antibiotic - a substance produced by a fungus which diminishes the growth of bacteria
    • 3 types of antimicrobials:
      • antiseptics used on living tissue
      • disinfectants used on non-living surfaces
      • antibiotics
    • antimicrobials - compounds that inhibit the growth of bacteria
    • antibiotic resistance - the situation in which a microorganism that has previously been susceptible to an antibiotic is no longer affected by it
    • antigen - a molecule that causes the immune system to produce antibodies against it
    • antibody - an immunoglobulin (protein) produced by the immune system in response to antigens that recognises and destroys antigens
    • vector - a person, animal or microbe (living organism) which carries and transmits an infectious pathogen onto another living organism
    • toxin - a small molecule made in cells or organisms, that causes damage to the host (toxins often affect macromolecules eg. enzymes)
    • antigenic type - organisms with very similar surface proteins or antigens, often subgroups or strains of a microbial species
    • fill in the table
      A) pathogenic
      B) infectious
      C) carrier
      D) disease reservoir
      E) endemic
      F) epidemic
      G) pandemic
      H) vaccine
      I) antibiotic
      J) antibiotic resistance
      K) antigen
      L) antibody
      M) vector
      N) toxin
      O) antigenic type
    • complete the table
      A) gram negative
      B) gut lining
      C) toxins
      D) dehydration
      E) water
      F) water treatment
      G) rehydration
      H) antibiotics
      I) bacteria
      J) lymph nodes
      K) airborne
      L) antibiotics
      M) variola major virus
      N) fluid filled blisters
      O) contact
      P) vaccine
      Q) virus
      R) respiratory tract
      S) airborne droplet infection
      T) good hygiene
      U) vaccine
      V) protoctistan parasite
      W) liver
      X) fever
      Y) vector
      Z) anopheles mosquitos
      [) prevent the vector
      \) kill the parasite
      ]) mutates
    • gram negative bacteria
      • thin peptidoglycan cell wall
      • layer of lipopolysaccharide - protects bacterial cell against lysozyme and penicillin type antibiotics
      • Gram staining technique - red
    • gram positive bacteria
      • thick peptidoglycan cell wall
      • no lipopolysaccharide layer
      • Gram staining technique - purple
      • susceptible to lysozyme and penicillin
    • microorganisms and parasites in the human body are only harmful if:
      • they secrete toxins
      • their population increases too much
      • they are transferred to an inappropriate part of the body
    • E. coli in the large intestine synthesise vitamin K, but in the stomach and small intestine they can cause gastro-intestinal disease
    • mites in the hair follicles of eyelashes eat dead cells, however, when eye make-up is not removed their population can increase and cause inflammation
    • entamoeba (protoctistan) graze on dead cells of gums, they can reproduce rapidly and cause gingivitis if the gums arent brushed enough
    • most microorganisms and parasites on or in the body contribute to general health and have a mutualistic relationship with the host