Chapter 12 - communicable diseases Flashcards
Communicable disease
A disease that can be spread from organism to organism via a pathogen
Foreign ( non-self)
not your own body’s cells and molecules, identified via foreign antigens
Self
The body’s own cells and molecules
Pathogen
microorganisms that cause disease
Active immunity
Resistance to a disease resulting from the activities of an individuals own immune system whereby a antigen induces plasma cells to produce antibodies
AIDS
The disease caused by HIV, characterised by a very low t helper cell count
Allergen
A normally harmless substance that causes the immune system to produce an immune response
Allergy
The response of an inmune system to an allergen such e.g hay-fever
Antibiotic
A substance produced by a living organism that can destroy or inhibit the growth of microorganisms
Antibiotic resistance
The development in microorganisms of mechanisms that prevent antibiotics from killing them
Antibody
A protein produced by lymphocytes in the response of an appropriate antigen, bonds with antigens to form antibody-antigen complexes
Antigen
A molecule that triggers and immune response by lymphocytes
Antigen-presentation
When an antigen presenting cell e.g. phagocyte displays foreign antigens on their own cell surface membranes
Antigenic variability
Pathogen may mutate frequently so that its antigens change suddenly rather than gradually which means vaccines become ineffective because the new antigens on the pathogen are no longer recognised by the immune system
