Immune System Flashcards
Role of Vaccines
(in preventing diseases)
- Non disease causing pathogen introduced into an organism
- Stimulates immunity
- Produces antibodies
How the general defense system fights infection
- Skin
- Clotting
- Sweat Glands
Passive Immunity
Antibodies introduced into body
(e.g child recieves antibodies from breastmilk)
Antibodies
Chemicals made by white blood cells in response to antigens
Anti-biotics
Chemicals made by micro-organisms used to kill other micro-organisms
Immunity
Resistance to disease
e.g of defense mechanisms in the body
- Dead cells in skin - physical or impenetrable barrier
- Sweat - contains chemicals that kill micro-organisms
Role of Lymphoctytes in immunity
- B-cells recognise antigen
- Antibodies produced
- Helper T-cells stimulate B-cell production
- Killer T-cells attack infected cells
Active immunity
e.g Vaccination
Pathogen
A disease causing organism
(e.g bacteria, fungi)
Non-specific immune system
blocks or neutralises invading pathogens
Specific immune system
identify and target pathogens
Phagocytes
Specialised white blood cells engulf pathogens
Macrophages
Long lasting phagocytes in lymph tissue and the spleen
Complement proteins
Proteins which attract and burst pathogens in the blood
Interferons
A group of proteins produced in response to viral infection
Antigen
Pathogen proteins that cause the production of antibodies
How antibodies kill Pathogens
- They prevent virus/bacteria entry into cells.
- Cause the ‘clumping’ of pathogens
- Trigger complement proteins
- Pathogen cells burst
- They bind to specific antigens allowing the pathogen to be destroyed by lymphocytes
T- Cells
- Killer Ts - produce perforin which attacks abnormal body cells
- Helper Ts - Stimulate division of correct B cells
- Suppressor Ts - prevent an overreaction
- Memory Ts - stimulate Memory and Killer T cells
Induced Immunity
The ability to resist disease caused by specific pathogens by the production of antibodies
Vaccination
The administration of a non-disease-causing dose of a pathogen or part of a pathogen which causes active immunity
