Immunity Flashcards
Function of immune system
Body’s defense against
1. pathogens (viruses, bacteria, fungi, parasites)
2. environmental pathogens (poison ivy)
3. toxins
4. abnormal body cells (cancer)
Immunity is…
The ability to resist infection and disease
What is innate (nonspecific) defenses
Immediate response to harmful agents that doesn’t require a previous exposure to a foreign substance
What responds first in innate defenses?
Skin, mucus membranes, inflammation, GI system, cellular response
True or False? We are born with innate defenses
True
What role do adaptive (specific) defenses play?
Identifies, attacks, reinforces, and amplifies immunity to a SPECIFIC pathogen
What is a major player in the adaptive immune defense?
Lymphocytes
True or False? adaptive immune defenses develop with time and exposure
True
Where do T-lymphocytes mature?
Thymus
Where do B-lymphocytes mature?
Bone marrow
What is inflammation?
immediate, local, and non-specific response
response is to injury, not just infection (ex: allergy, twisted ankle)
increased blood flow to the site, increase capillary permeability. attracts cells of immunity
What role does histamine, prostaglandins, leukotrienes, and bradykinin in inflammation?
Causes vasodilation and increase in capillary permeability
Effects of histamine
Increase capillary permeability, vasodilation, bronchoconstriction, increase nasal and mucus secretion, stimulates sensory receptors (ex: increase itching)
What could go wrong if inflammation goes too far?
damage to healthy cells, low blood pressure from vasodilation, swelling in brain or larynx (inappropriate swelling)
Acute inflammation
either resolved, leads to scarring/fibrosis, can progress to chronic inflammation
Chronic inflammation
result of recurring or progressive acute inflammatory responses
this response often has infiltration of macrophages, lymphocytes, plasma cells, attempted connective tissue repair involving angiogenesis and fibrosis (tissue damage)
Examples: rheumatoid arthritis, lupus, chronic pancreatitis, chronic hepatitis
What cells are the first to respond during innate immunity?
Neutrophils
What cells fight worms/parasites?
Eosinophils
Where are monocytes found and what do they become?
In blood; become macrophages and dendritic cells
What are dendritic cells?
antigen presenting cells
what are the 3 protein systems?
complement, clotting, kinin
what does the complement system do?
opsonizes pathogens (coats bacteria and provides handles for grabbing onto), kills pathogens by perforating cell, amplifies inflammatory response
What does the kinin system do?
enhances inflammatory response (vasodilation, smooth muscle contraction, vascular permeability), along with prostaglandins (inflammatory response) stimulates pain receptors
what are the two antigen presenting cells and what do they do
dendritic cells and macrophages; digest invading microbe and present antigen to lymphocytes in lymphoid organs
What is produced after first exposure to pathogen?
Memory t and b cells
what makes up cellular immunity and where do the cells mature?
T-cells, CD8 cells (killer t cells), CD4 cells (helper t cells), mature in thymus
what cells make up humoral immune response and where do they mature
b-cells (produced by plasma cells), mature in bone marrow
IgG
most effective antigen, can cross placenta