The Immune System Flashcards
What is innate immunity?
aka “nonspecific immunity”; composed of defenses that are always active against infection but lack the ability to target specific invaders
What is adaptive immunity?
aka “specific immunity”; the defenses that target a specific pathogen; slower to act but maintains an immunological memory of the an infection to mount a faster attack in subsequent infections
What does bone marrow do?
produces leukocytes
What does the spleen do?
location of blood storage and activation of B cells
What is humoral immunity?
A division of adaptive immunity in which the antibodies dissolve and act in the blood instead of the cell
Where is the thymus?
in front of the pericardium, the sac that protects the heart
What do B-cells do?
turn into plasma cells to produce antibodies as part of adaptive immunity
What do T-cells do?
coordinate the immune system and directly kill virally infected cells
What do lymph nodes do?
provides a place for immune cells to communicate and mount an attack; B cells can be activated as well
What are the gut-associated lymphoid tissue (GALT)?
tonsils, adenoids, Peyer’s patches in the small intestine, and lymphoid aggregates in the appendix
What are the organs associated with the immune system?
(1) Lymph nodes
(2) Bone marrow
(3) Thymus
(4) Spleen
Hematopoietic stem cells give rise to _______, ________, ______ and _______.
granulocytes; agranulocytes; red blood cells; platelets
What are the three types of granulocytes?
neutrophils, eosinophils, basophils
What are two types of agranulocytes?
lymphocytes and monocytes
Monocytes become ____ when they move from blood to tissue.
macrophages
What are macrophages called in the CNS?
microglia
What are macrophages called in the skin?
Langerhans cells
What are macrophages called in the bone?
osteoclasts
What are the two categories of specific immunity?
Humoral - driven by B cells and antibodies
Cell-mediated - driven by T cells
What are defensins?
antibacterial enzymes found on the skin
What is lysozyme?
a nonspecific bacteria enzyme secreted in tears and saliva
How does the GI tract contribute to the immune system?
(1) Acid eliminates a lot of bacteria
(2) Large gut bacteria population keeps competitors at bay
What is the complement system?
many proteins in the blood that act as a nonspecific defense; they punch holes in the walls of the bacteria, making them osmotically unstable
Classical vs alternative pathway
Classical requires binding of an antibody to a pathogen to activate the complement system and alternative does not