Diseases And Immunity Flashcards
What is a Pathogen?
A disease causing organism
What is a transmissable diesease?
A disease which can be passed from one host body to another
eg: Directly via blood and bodily fluids
eg: Indirectly via contaminated surfaces, animals and air
Types of body Defenses
Mechanical, Chemical Barriers and Cells
Examples of Mechanical Barriers
Nostrils containing hair to trap dust particles
Skin has a thick outer layer of dead cells
Examples of Chemical Barriers
Sticky Mucus which can trap pathogens
In stomach hydrochloric acid secreted to help kill bacteria
Examples of Cells
Cells that take in and digest the pathogens by phagocytosis.
Others produce antibodies which exterminate pathogens.
Vaccination against disease helps antibodies respond quickly.
What is an Antibody?
A protein molecule which fits into another molecule
What are pathogen molecules called?
They are called antigens
Function of antibodies
lock on to antigens leading to extermination of pathogen/ marking of pathogens by phagocytes
What is Active Immunity?
Defence against a pathogen by antibody production in the body
How is active immunity gained?
It is gained after an infection by a pathogen or vaccination
Process of Vaccination
Harmless pathogen given which has antigens.
Antigens trigger a response by lymphocytes which produce antibodies.
Memory cells are produced to give long immunity
What is passive immunity?
Short-term defence against pathogen by antibodies provided from another indiviual
