The Immune System Flashcards
____ is the ability to resist damage from pathogens and disease
immunity
____ immunity has both external and internal defenses and is also nonspecific
innate
___ immunity has internal defenses involving the recognition and memory of pathogens and is specific to the type of pathogen
adaptive
___ and ___ are physical barriers that function for external innate immunity
skin and mucous membranes
___ is an anti-microbial peptide released by sweat glands
dermicidin
___ contains anti-microbial fatty acids
sebum
Mucous membrane cells secrete mucus to _____
trap pathogens and debris
Skin secretions are ___ and __ to bacteria
acidic and toxic
____ have lysozymes within lacrimal fluid to damage bacterial cell walls
tears
The digestive tract has what 3 things to provide external innate immunity?
1-lysozymes in saliva
2-HCl in stomach
3- normal flora from intestines
How does the respiratory tract provide external innate immunity?
It secretes mucous which traps pathogens and has cilia in the epithelium that moves the mucus to the throat
____ is a glycoprotein within milk, saliva, tears, and nasal secretions that iron can bind to
lactoferrin
How does lactoferrin inhibit pathogen activity?
Lactoferrin binds to iron and oxidizes microbes
How does the urogenital tract provide external innate immunity? 2 ways
1-The pH of urine (~4.0) kills pathogens
2-the lactic acid within the vagina kills pathogens
What are the 2 phagocytic cells of internal innate immunity?
neutrophils and macrophages
What are the 4 (non-phagocytic) cells of internal innate immunity?
natural killer cells, basophils, eosinophils, mast cells
Hematopoiesis occurs in the ____
bone marrow
Lymphocytes are what 3 cells?
T, B, natural killer cells
Megakaryocytes supply what cells?
platelets
Which white blood cell is normally the first to arrive at the site of infection?
neutrophils
Neutrophils release chemical signals, ____ and ____, to recruit other immune cells
cytokines and chemokines
Neutrophils also release _____, which are antimicrobial peptides active against many bacteria, fungi, and viruses
alpha defensins
__ is a collection of dead neutrophils and microorganisms, dead tissue, and fluid
pus
Neutrophils release lysozymal enzymes into the _____ to kill microorganisms, but it also kills surrounding tissue
extracellular space
____ is the process where neutrophils follow chemical trial to the infection site
chemotaxis
In ____, the inflamed capillary endothelial cells develop cell adhesion molecules for neutrophils to attach (prompted by chemotaxis)
margination
Vasodilation and increased permeability of capillaries allows for _____, where neutrophils flatten and squeeze out of capillaries between endothelial cells
diapedesis
When monocytes leave the blood they become ___ or ___
macrophages or dendritic cells
Macrophages usually arrive after neutrophils and perform what function?
they phagocytose neutrophil remains, microorganisms, and fragments of the damaged tissue
What are the 3 places macrophages are normally located?
1-beneath skin and mucous membranes
2-around blood and lymphatic vessels
3-within the tonsils, lymph nodes, spleen, liver, lungs, and CNS
Macrophages release ____ (antimicrobial peptides), ___ (toxic to many bacteria), ____ (signaling molecules), ____ (actors in the inflammatory process) and ____ (induce fever)
alpha defensins; NO; interferons; complement proteins; pyrogens
____ are plasma proteins synthesized by the liver hepatocytes and monocytes/macrophages and found normally within the blood in an inactive form until they are activated
complement proteins
___ is a process that coats substances or cells to increase adherence of phagocytes
opsonization
The complement system activates MAC which does what?
MAC is a multiunit protein that attaches to a foreign cell and creates a large pore in the cell membrane to allow the free diffusion of water and solutes into and out of the cell, destroying the cell