Immune system Flashcards
What is the immune system?
A system of cells, tissues, and organs that is dispersed widely throughout the body to defend against pathogens
Leukocytes (white blood cells)
Most are NOT in blood, immune cells
What are the two leukocyte examples?
Macrophages and lymphocytes
Macrophages
Engulf foreign materials/debris, NOT specific to one antigen, presents antigen on cell surface
Lymphocytes
Recognizes and attacks one specific type of antigen, must be activated by a macrophage first
Lymphoid
Reticular CT with lots of lymphocytes, common in places where pathogens may enter
What is an example of a lymphoid?
MALT = mucosa-associated lymphoid tissue
Where are the primary lymphoid organs?
(where lymphocytes are made) in the thymus and red bone marrow
Where are the secondary lymphoid organs?
(contain mature lymphocytes) in lymph nodes, tonsils, appendix, spleen, peyer’s patches
