Immunity Flashcards
what are the types of immunity?
active and passive
what is active immunity?
Protection by adaptive immune response Individual’s immune system is activated against an antigen Time to develop Immunological memory Immunity develops over weeks
what is passive immunity?
Transfer of antibodies
Immediate immunity
Does not last as no memory
Antibodies degrade overtime
what is natural passive immunity?
Mother to foetus through placenta or milk
Weeks of months of protection which own immune system develops
what is artificial passive immunity?
Receiving antibodies in antiserum from another organism
Antiserum contains specific antibodies
Serum is the fluid of blood
Useful if death will occur before the immune system kicks in
Can suppress active immunity when it is harmful
Snake bite
what is natural active immunity?
Immunological memory from an infection
what is artificial active immunity? types?
Administration of antigens to induce the active immune response
Vaccination
Vaccine is altered or weakened or killed or inactivated
Boosters needed to activate a stronger secondary response
- live attenuated vaccines
- inactivated vaccines
- subunit vaccines
what are live attenuated vaccines? advantages, disadvantages
Weakened living microbe through repeated culturing
Advantage: long lasting as a strong immune response was induced, producing many antibodies
Disadvantage: not safe for people with weak immune systems, cross placenta in pregnant woman and infect baby
what are inactivated vaccines? advantages, diadvantages
Aka killed vaccines
Inactivated by heat, chemicals, radiation
advantages: result in production of many different antibodies, safe for all
disadvantages: stimulate a weak response so require a booster
what are subunit vaccines? advantages, disadvantages
Contain parts of microbes
Advantages: safe, stable, easier to store
disadvantages: need boosters to be more powerful
what is herd immunity?
For immunisation to be effective, a sufficient number of people need to be vaccinated
Essential for those who cannot be vaccinated
what is the allergic reaction? how dangerous? what happens? what antibody is involved?
Allergic reaction
Rapid overreaction to antigens that are harmless (allergens)
Pollen
Mild to life-threatening
Pollen allergy or hay fever is a reaction to antigens on pollen
Release of histamine from mast cells
Antibody immunoglobulin E (IgE) is produced by plasma cells
IgE binds to mast cells and when allergen binds across two antibodies (bridging the gap) mast cell releases histamine
what does the release of histamine cause?
Blood vessel dilation
Increase of blood vessel permeability
Contraction of muscles in air ways
Fluid-secreting cells- teary eyes, runny nose which expel antigens
what are autoimmune diseases?
Adaptive immune system response directed against self-antigens
T cells attack tissues directly
B cells work indirectly, relating antibodies
what are the types of autoimmune disease?
Organ-specific are located in a localised area
Generalised autoimmune diseases are located throughout the body