unit 4: defense mechanisms Flashcards
Protect against disease-causing agents
pathogens
make up the immune system
innate and adaptive immunity
two types of pathogens
-innate (nonspecific) immunity
-adaptive (specific) immunity
this immunity is inherited
innate
this immunity is learned from exposure to specific pathogens; function of lymphocytes
adaptive
cause disease in their host. 5 main types include bacteria, viruses, fungi, parasites, prions
pathogens
first line of defense- fast and present from birth. there are two types:
-first line (physical and chemical barriers)
-second line (internal defense)
innate immunity
innate immunity of skin includes
tight junctions
what does mucosa secrete
mucous - anti microglial
upper respritory
mucosa
what wbc are in innate immunity
-phils and monocyte/macrophages
innate immunity includes
tight junctions (epithelium), mucosa, wbc, stomach acid
includes external and internal defenses
innate immunity
serves as a first line of defense against pathogens
innate immunity
cells that engulf and kill
macrophages and neutrophils
cells distinguish “self” from “nonself” using — unique to the pathogens
pathogen associated molecular patterns (pamps)
associated with pathogens.
-specific
-“this isnt me”
-antigens
pamps
these cells respond by secreting chemokines to recruit more immune cells or activate specific immune cells
pamps
small protein molecules produced by the immune system that act as chemoattractants, guiding immune cells to sites of infection or inflammation. They play a crucial role in directing immune cell migration, helping the body fight off infections, inflammatory conditions, and other diseases.
chemokines
detected by pattern recognition receptors on immune cels like macrophages and dendritic cells
pamps
tissue damage that causes necrosis
local inflammation
when the immune system exposed to damps
local inflammation
stimulates innate immune responses and inflammation
local inflammation
When tissue is injured (like from a cut, burn, or lack of oxygen), some of the cells die in an uncontrolled way — this is called —-. It releases the cell contents into the surrounding tissue, which is abnormal and signals that something’s wrong.
necrosis
When those damaged or dying cells break apart, they release internal molecules that aren’t usually outside the cell. These are called
damps- danger associated molecular patterns
act as alarm signals that tell the immune system theres damage, even if theres no infection
damps
what happens when damps are detected by immune cells like macrophages or dendritic cells
they activate the innate immune system
what happens when damps activate the innate immune system
the activation loeads to local inflammation at the site of damage- meanning inflammation is happening in that specific, injured area
“silent” cell death.
-controlled and clean.
-cells die without triggering inflammation.
-the cell shrinks, then phagocytes come clean it up
-no damps released
apoptosis
“explosive” cell death
-not programmed and accidental
-helps when apoptosis is blocked or not possible
-cell swells and bursts, releasing damps
necroptosis
