Specific defence system (the immune system) Flashcards
Define specific defence system
It attacks particular (specific) pathogens
How does this system work? (2)
It works by:
the production of antibodies
white blood cells destroying body cells that have been infected with a particular pathogen
Where are monocytes and lymphocytes formed?
In the bone marrow
Once the monocytes and lymphocytes are formed, what happens to them?
They are moved from the bone marrow into blood vessels and into parts of the lymphatic system (lymph vessels and nodes, spleen and the thymus gland)
What do monochytes develop into?
macrophages
What do macrophages do?
They recognise foreign molecules (antigens) that are present on the surface of pathogens.
What happens when a macrophage digests a pathogen?
antigens from the pathogen are normally displayed on the surface of the macrophage
Define antigen
It is a foreign molecule that stimulates the production of antibodies
In what two ways do lymphocytes fight infection?
- Some attack body cells that display antigens on their surface.
- Others produce antibodies