Term
| What are the bodies two mechanisms of defense? |
|
Definition
1. Innate defense mechanisms – first line of defense
2. Adaptive defense mechanisms – second line of defense (if the invader is able to overcome the first-line) |
|
|
Term
| Innate defense mechanisms |
|
Definition
A) These defenses are non-specific and inherited
B) Examples:
1) Physical barriers
2) Chemical defenses
3) Normal bacterial flora
4) Cell communicators (cytokines)
5) Sensor systems (complements)
6) Phagocytosis
7) Fever |
|
|
Term
| Adaptive defense mechanisms |
|
Definition
A) These defenses are specific, learned, and have memory
B) Primarily involve 2 types of WBC’s
1) T-lymphocytes (T cells)
2) B-lymphocytes (B cells) |
|
|
Term
| Cells of the immune system |
|
Definition
Granulocytes
Agranulocytes |
|
|
Term
|
Definition
Neutrophils
Basophils
Eosinophils |
|
|
Term
|
Definition
Most abundant
1) a.k.a. polymorphonuclear leukocytes (PMNs, polys, segs)
2) phagocytes |
|
|
Term
|
Definition
least numerous
1) involved in allergic reactions
2) release histamine, heparin, leukotrienes, and prostaglandins
a) increase capillary permeability during inflammation
3) were once thought to develop into mast cells which have the same function |
|
|
Term
|
Definition
| combat parasitic worm infections |
|
|
Term
|
Definition
|
|
Term
|
Definition
differentiate into two types of cells within the body tissues:
1) Macrophage – phagocytes
a) accumulate within the liver, spleen, lymph nodes, lungs, and peritoneal cavity
2) Dendritic cells – phagocytes
a) important in adaptive immunity
b) act as antigen-presenting cells (APCs) |
|
|
Term
|
Definition
a) require APCs
b) four main functional types:
i) cytotoxic T-cells
ii) helper T-cells
iii) suppressor T-cells
iv) memory T-cells |
|
|
Term
|
Definition
a) 2 functional types
i) plasma cells
ii) memory B cells |
|
|
Term
|
Definition
not specific
a) they kill cells that have been bound by antibodies or cells that exhibit abnormal traits
b) use perforins & granzymes to destroy the cells |
|
|
Term
|
Definition
B cells
T Cells
Natural Killer cells |
|
|
Term
|
Definition
A) The dermis is contains tightly woven fibrous connective tissues
B) The epidermis possess a water-repelling protein called keratin which makes the
skin an arid environment
1) In addition the outer most layers continually slough off, taking microbes with them |
|
|
Term
|
Definition
Physical barriers
Chemical defenses
Normal bacteria flora
cell communicators
Sensor systems
Phagocytosis
Fever |
|
|
Term
|
Definition
--Physical barrier--
A) line the digestive, respiratory, and urogenital tracts
B) constantly bathed in mucus and other body secretions that help trap & wash away microbes
C) peristalsis also helps to move microbes toward body openings where they are more easily eliminated
D) cilia propels microbes toward body openings as well |
|
|
Term
| Lysozymes (chemical defense) |
|
Definition
A) enzymes that degrade peptidoglycan
B) found in several body secretions including tears, saliva, mucus, perspiration, tissue
fluids, blood, and phagocytic vesicles
C) very effective against Gram (+) bacteria |
|
|
Term
| Peroxidase enzymes (chemical defense) |
|
Definition
A) found in saliva and milk as well as tissue fluids and phagocytic vesicles
B) break down hydrogen peroxide to produce potent oxidizing agents
C) especially potent against catalase-negative organisms |
|
|
Term
|
Definition
enzyme that neutralizes the products of hydrogen peroxide breakdown
(peroxidase enzyme) |
|
|
Term
| Lactoferrin (chemical defense) |
|
Definition
A) an iron-binding protein found in saliva, mucus, and milk
B) makes iron, an essential element, unavailable for microbes to use |
|
|
Term
| Defensins (chemical defense) |
|
Definition
A) antimicrobial peptides found in mucus membranes and phagocytic cells
B) insert themselves into bacterial cell membranes creating pores that disrupt the membrane’s integrity |
|
|
Term
| High acidity (chemical defense) |
|
Definition
low ph
A) urine, gastric juices, and vaginal secretions |
|
|
Term
|
Definition
1. the population of microorgs normally growing on body surfaces of healthy individuals
A) create competition for nutrients
B) some produce antimicrobial agents
C) may block binding sites that invaders might normally use to infect host cells
2. Examples
A) Propionibacterium
1) live in the hair follicles & produce a fatty acid secretion that inhibits growth of many disease causing species
B) Escherichia coli
1) produce antimicrobial toxins in GI
C) Lactobacillus
1) produce lactic acid in vagina causing pH to be too low for other bacteria to survive |
|
|
Term
|
Definition
1. allow cells to communicate with their environment and each other
2. two components: surface receptors and cytokines |
|
|
Term
|
Definition
cell's ears
1) integral membrane proteins
2) only bind to specific chemicals |
|
|
Term
|
Definition
1) released by cells in response to invasion
2) bind to surface receptors to initiate a change in that cell
a) usually growth, differentiation, movement or death
3) 5 important groups of cytokines
a) Chemokines – 50 or more diff substances that stimulate chemotaxis
b) Interferons – produced by virus-infected cells
i) protect surrounding cells
c) Colony-Stimulating Factors (CSFs) – important in the multiplication &
differentiation of leukocytes
d) Interleukins (ILs) – produced by leukocytes with at least 18 diff types
i) function in innate immunity, inflammation, & adaptive immunity
e) Tumor Necrosis Factors (TNFs) – kill tumor cells, initiate inflammatory
responses, & programmed cell death |
|
|
Term
|
Definition
1. Detect the presence of microbial invasion or tissue damage
2. Two main types: toll-like receptors & complements |
|
|
Term
|
Definition
1) located on the membranes of certain host cells (some immune cells, some not)
2) detect specific chemicals/structures associated with microorganisms and initiate an immune response
a) ex. peptidoglycan, flagella, specific DNA sequences |
|
|
Term
|
Definition
1) series of normally inactive, circulating proteins
2) they increase the activity of antibodies
3) there are 9 main complements (C1-C9)
4) become active in the presence of certain stimuli
5) complement activation leads to 3 protective outcomes: inflammation, foreign cell lysis, opsonization. |
|
|
Term
| inflammation (complement) |
|
Definition
| C3a and C5a increase permeability and act as chemoattractants |
|
|
Term
| foreign cell lysis (complement) |
|
Definition
i) C5b, C6, C7, C8, and C9 aggregate within the membrane creating “holes”
ii) Gram (-) bacteria are most susceptible |
|
|
Term
| opsonization (complement) |
|
Definition
| C3b “coats” the surface of the foreign cell making it sticky and more easily phagocytized |
|
|
Term
|
Definition
A) chemotaxis
B) adherance
C) engulfment
D) phagolysosome formation
E) destruction & digestion
1) residual bodies
F) exocytosis of residual bodies |
|
|
Term
|
Definition
| by-products of the destruction of the antigen |
|
|
Term
|
Definition
1. one of the strongest indicators of infectious disease
2. causes cells to sequester zinc
3. thought to decrease bacterial metabolism and increase the host’s defense responses
4. caused by pyrogens that act on the hypothalamus to increase body temp
5. pyrogens fall into 2 categories: endogenous & exogenous |
|
|
Term
|
Definition
1) produced by the host
2) ex. cytokines |
|
|
Term
|
Definition
1) produced by invading microbe
2) ex. bacterial toxins |
|
|
