Chapter 21 (Lecture)

Question 1

ability of the body to resist many agents (both living and nonliving) that can cause disease; resistance to disease

Answer 1

immunity

Question 2

• first line of defense: surface barriers such as intact skin and mucosae
• second line of defense (internal): antimicrobial proteins, phagocytes, fever, NK cells, and other cells; hallmark is inflammation
• NO MEMORY

Answer 2

innate (nonspecific) immune system

Question 3

• takes considerably longer to mount
• humoral immunity
• cellular immunity
• MEMORY; each response is unique, and second exposure is quicker

Answer 3

adaptive (specific) defense system

Question 4

• a functional system rather than an organ system in an anatomical sense
• structures are a diverse array of molecules plus trilions of immune cells (especially lymphocytes) that inhabit lymphoid tissues and circulate in bodily fluids

Answer 4

immune system

Question 5

harmful or disease-causing microorganisms

Answer 5

pathogens

Question 6

benefits of keratin

Answer 6

resistant to most weak acids, alkalis and bacterial enzymes

Question 7

protective chemicals of the innate immune system

Answer 7

• acid (acid mantle)
• enzymes
• mucin
• defensins
• lipids, sebum and dermicidin

Question 8

protective mechanism: normally acidic pH inhibits bacterial growth; cleanses the lower urinary tract as it flushes from the body

Answer 8

urine

Question 9

protective mechanism: continuously lubricate and cleans eyes (tears) and oral cavity (saliva): contain lysozyme, an enzyme that destroys microorganism

Answer 9

tears, saliva

Question 10

protective mechanism: inhibits growth of most bacterai and fungi in female reproductive tract

Answer 10

acid mantle of the vagina

Question 11

protective mechanism: contains concentrated hydrochloric acid and protein-digesting enzymes that destroy pathogens in the stomach

Answer 11

gastric juice

Question 12

protective mechanism: propel debris-laden mucus away from nasal cavity and lower respiratory passages

Answer 12

cilia

Question 13

protective mechanism: filter and trap microorganisms in respiratory and digestive tracts

Answer 13

nasal hairs

Question 14

protective mechanism: traps microorgansim in respiratory and digestive tracts

Answer 14

mucus

Question 15

protective mechanism: skin secretions (sweat and sebum) make epidermal surface acidic, which inhibits bacterial growth; also contain various bactericidal chemcials

Answer 15

acid mantle of skin

Question 16

vesicle formed as a result of phagocytosis

Answer 16

phagosome

Question 17

• phagocytes
• about 126B/day produced
• usually the first WBC to make it to an infection
• 1 time use

Answer 17

neutrophils

Question 18

made up of dead neutrophils, microbes, pathogens

Answer 18

pus

Question 19

• monocytes in blood, this in tissue
• leave blood and increase in numbers at site of infection
• cleanup crew
• dendritic cells, microglia, alveolar, hepatic

Answer 19

macrophages

Question 20

• mobile
• release factors that attract more WBCs

Answer 20

basophils

Question 21

• immobile
• are found near sites of possible pathogen influx
• release chemotaxic factors
• can also phagocytize bacteria

Answer 21

mast cells

Question 22

factors that attract more WBCs

Answer 22

chemotaxic factors

Question 23

act as moderators of inflammatory response and kill parasites by releasing enzymes all over them

Answer 23

eosinophils

Question 24

• B cells and T cells
• Natural Killer Cells (NKC)

Answer 24

lymphocytes

Question 25

recognize tumor and cancerous cells in general

Answer 25

NKC (natural killer cells)

Question 26

* prevents the spread of damaging agents to nearby tissues * disposes of cell debris and pathogens * sets the stage for the repair process

Answer 26

inflammatory process

Question 27

cardinal signs of inflammation

Answer 27

* redness * heat * swelling * pain

Question 28

* happens after first exposure, involves the creation of killer T cells and memory cells * usually takes about 3-7 days, and you will feel sick during this time

Answer 28

primary response

Question 29

occurs upon a repeated exposure to the same antigen or a similar formand the memory clels recognize it and the response is faster and of greater magnitude

Answer 29

secondary response

Question 30

long-lived and require less activation to respond than do other APCs

Answer 30

memory T cells

Question 31

* production is regulated by helper T cells and antigen presenting cells * once activated, proliferate and produce Killer Ts and memory T cells

Answer 31

cytotoxic T cells

Question 32

effects of cytotoxic T cells

Answer 32

* cause cells to lyse (contact killing) by releasing perforins * cause the release of cytokines that attract cells such as macrophages and WBCs (inflammatory response)

Question 33

caused by the release of histamines, prostaglandins, etc. from the injured tissues

Answer 33

vasodilation

Question 34

allows protein rich fluid to seep into the injured region from the blood vessels

Answer 34

vascular permeability

Question 35

which factors cause edema in the injured area

Answer 35

vasodilation and vascular permeability

Question 36

steps of phagocyte mobilization

Answer 36

1. leukocytosis 2. margination 3. diapedesis 4. chemotaxis

Question 37

follows chemical signals to injured site

Answer 37

chemotaxis

Question 38

# true or false: inflammatory response can be localized or systemic in nature

Answer 38

true

Question 39

functions of antimicrobial proteins

Answer 39

* preventing entrance to cell * vasodilation * increased permeability * attracting WBCs * increasing phagocytosis

Question 40

* protects body against viral attack * mobilize NK cells * can be released by lymphocytes to cause widespread immune mobilization

Answer 40

interferon

Question 41

virus infected cells produce interferon which

Answer 41

stimulates neighboring cells to produce antiviral proteins

Question 42

A group of bloodborne proteins, which, when activated, enhance the inflammatory and immune responses and may lead to cell lysis.

Answer 42

complement system

Question 43

classical complement pathway is stimulated by

Answer 43

antibodies

Question 44

alternate complement pathway is stimulated by

Answer 44

factors C3 which break down into different compounds

Question 45

complement works in which response

Answer 45

both the innate and adaptive resopnses

Question 46

a systemic response that involves the release of pyrogens

Answer 46

fever

Question 47

events of phagocytosis

Answer 47

1. phagocyte adheres to pathogens or debris (using receptors) 2. phagocyte forms pseudopods that eventually engulf the particles, forming a phagosome 3. lysosome fuses with the phagocytic vesicle, forming a phagolysosome 4. toxic compounds and lysosomal enzymes destroy pathogens 5. sometimes exocytosis of the vesicle removes indigestible and residual material

Question 48

* wander throughout the tissue spaces in search of cellular debris or "foreign invaders"

Answer 48

free macrophages

Question 49

such as stellate macrophages in the liver, are permenant residents of particular organs

Answer 49

fixed macrophages

Question 50

when neutrophils enter blood from the bone marrow

Answer 50

leukocytosis

Question 51

neutrophils cling to the capillary wall

Answer 51

margination

Question 52

neutrophils flatten and squeeze out of capillaries

Answer 52

diapedesis

Question 53

steps of interferon release/production

Answer 53

1. virus enters cell 2. interferon genes switch on 3. cell produces interferon molecules 4. interferon binding stimulates cell to turn on genes for antiviral proteins

Question 54

* antigen-antibody complex * C1, C4, C2 complex

Answer 54

classical pathway of complement system

Question 55

coats pathogen surfaces, which enhances phagocytosis

Answer 55

opsonization

Question 56

steps to contact killing

Answer 56

1. cytotoxic t cell binds tightly to the target cell when it identifies foreign antigen on MHC I proteins 2. Tc releases perforin and granzyme molecules from the granules by exocytosis 3. perforin molecules insert into the target cell membrane, polymerize, and form transmembrane pores similar to thsoe produced by complement activation 4. granzymes enter the target cell via the pores. once inside, the proteases degreade cellular contents, stimulating apoptosis 5. Tc detaches and searches for another prey

Question 57

steps TH cells use to help in humoral immunity

Answer 57

1. TH cells binds with the self-nonself complexes of a B cell that has encountered its antigen and is displaying it on MHC II on its surface 2. TH cell releases interleukins as a co-stimulatory signals to complete B cell activation

Question 58

steps of TH cells in cell-mediated immunity

Answer 58

1. previously activated TH cell binds dendritic cell 2. TH cell stimulates dendritic cell to express co-stimulatory molecules needed to activate CD8 cell 3. dendritic cell can now activate CD8 cel with the help of IL2 secreted by TH cell

Question 59

steps to the activation of T cells

Answer 59

* dendritic cells engulfs an exogenous antigen, processes it,, and displays its fragments on class II MHC protein * immunocompetent CD4 cell recognizes antigen-MHC complex. both T-Cell Receptor and CD4 protein bind to antigen-MHC complex * CD4 cells are activated, proliferate, and become memory and effector cells

Question 60

* fixes complement, often first produced * powerful agglutinogen

Answer 60

IgM

Question 61

secreted into tears and colostrum, protects body surfaces

Answer 61

IgA

Question 62

binding site on B-cells

Answer 62

IgD

Question 63

activates complement, found in plasma

Answer 63

IgG

Question 64

binds to mast cells and basophils, stimulates inflammation

Answer 64

IgE

Question 65

types of active immunity

Answer 65

* naturally acquired * artificially acquired

Question 66

types of passive immunity

Answer 66

* naturally acquired * artificially acquired

Question 67

types of humoral immunity

Answer 67

* active * passive

Question 68

immunity that comes from infection; contact w/ pathogen

Answer 68

naturally acquired active immunity

Question 69

acquired from vaccines; dead or attenuated pathogens

Answer 69

artificially acquired active immunity

Question 70

comes from antibiodies passed from mother to fetus via placenta; or to infant in her milk

Answer 70

naturally acquired passive immunity

Question 71

acquired from injection of immune serum (gamma globulin)

Answer 71

artificially acquired passive immunity

Question 72

why can B-cells act as APCs

Answer 72

their receptors are antibodies

Question 73

* dendritic cells, macrophages, activated B lymphocytes * engulf antigens and produce fragments on their surface attached to MHC complexes

Answer 73

antigen presenting cells

Question 74

* spontaneous activation * stabilizing factors B, D, and P * no inhibitors on pathogen surface

Answer 74

alternative complement pathway

Question 75

* secreted by macrophages and neutrophils exposed to foreign substances * stimulates the hypothalamus to make prostaglandin E

Answer 75

pyrogens (IL1)

Question 76

what is the role of prostaglandin E

Answer 76

raises the set point for the body's internal temperature

Question 77

how do NSAIDs reduce fever

Answer 77

by inhibiting PGE synthesis

Question 78

benefits of fever/pyrexia

Answer 78

* promotes interferon activity * elevate metabolic rate to promote healing * inhibit reproduction of pathogens

Question 79

anything above what internal temperature will cause delirium and higher temperature cause irreversible damage

Answer 79

105

Question 80

* found in macrophages, B cells, and monocytes * processed antigens will cause costimulation to occur

Answer 80

MHC II

Question 81

found in nucleated cells, causes red flag to be raised if they display a foreign antigen

Answer 81

MHC I

Question 82

* displayed by all body cells, usually by MHC I complexes

Answer 82

self antigens

Question 83

* region on the surface of an antigen that is immunogenic * simple antigens may have only one or two of these * more complex ones may have hundreds that bind and activate different types of antibody

Answer 83

antigenic determinants/epitopes

Question 84

usually polymers that are not deemed reactive by the body

Answer 84

implants

Question 85

* both immunogenic and reactive * viruses, bacteria, fungi, etc

Answer 85

complete antigens

Question 86

haptens, pet dander, poison ivy, cosmetics, perfumes

Answer 86

haptens

Question 87

reactive, but not immunogenic so they only cause a reaction if they bind to other proteins in our body

Answer 87

haptens

Question 88

* any molecule that triggers an immune response * usually have a fairly high molecular weight * complex molecules that are unique to individuals (proteins, polysaccharides, glycoproteins, glycolipids) * body usually only attacks "non-self"

Answer 88

antigens ## Footnote Ag, antigen generating

Question 89

* antigen-specific * systemic * memory * two major components: humoral and cell-mediated immunity

Answer 89

adaptive response

Question 90

which lymphocytes are responsible for humoral immunity

Answer 90

b cells

Question 91

which lymphocytes are responsible for cell-mediated immunity

Answer 91

T cells

Question 92

produced from lymphoblast precursors in red bone marrow

Answer 92

lymphocytes

Question 93

reach maturity in the bone marrow before being released

Answer 93

B cells

Question 94

immature T-cells migrate where before maturation

Answer 94

thymus

Question 95

* created in red bone marrow, but soon leave * mature in thymus gland--undergo positive and negative selection * after selection they colonize lymphatic tissue and organs everywhere in the body

Answer 95

T-cells

Question 96

if they do not react to foreign antigens or if they DO react to self antigens they are culled from the population

Answer 96

negative selection

Question 97

if they react to foreign antigen, but not to self antigen

Answer 97

positive selection

Question 98

* mature in bone marrow * undergo a similar type of seletion as T cells * once they are mature they colonize many of the same tissues as T cells

Answer 98

B cells

Question 99

overall goal of any cell that acts as an APC

Answer 99

interact the antigen and then stimulate the two arms of the specific immune response

Question 100

# true or false: T cells can detect antigens on their own

Answer 100

false

Question 101

the process wherein the MHC II complex of an APC binds with a helper T cell and this stimulaates the release of cytokines between the two cells which causes the helper T cells to either: * proliferate and produce more helper T cells * stimulate B or T cells

Answer 101

costimulation

Question 102

* most effective agianst intracellular microorganisms such as viruses, fungi, bacteria, and parasites * activation regulated by antigen-presenting cells and helper T-cells

Answer 102

T-cells

Question 103

types of T cells

Answer 103

* cytotoxic * helper * memory

Question 104

killer, CD8, or T8 t-cells

Answer 104

cytotoxic T cells

Question 105

CD4 T-cells, activate CD8 cells and also stimulate antibody mechanisms

Answer 105

helper T cells

Question 106

come from cytotoxic cells and remember the pathogens

Answer 106

memory T cells

Question 107

* have receptors on their surface for an antigen * when they are challenged by an antigen, activates specific receptors and begins stimulating them to divide

Answer 107

naive B cells

Question 108

rapidly creates plasma cells and memory cells

Answer 108

clonal selection of B cells

Question 109

secrete antibodies at rates up to 2000/s for 4-7 days

Answer 109

plasma cells

Question 110

long lived and retain the imprint of the antigen so they can respond almost immediately to future attacks

Answer 110

memory cells

Question 111

effects of antibodies

Answer 111

* neutralization * agglutination * precipitation * complement

Question 112

antibody can bind directly to the antigenic determinant and interfere with or deactivate the antigen

Answer 112

neutralization

Question 113

antibody can combine with the antigenic determinants on two antigens rendering them ineffective adn making them more susceptible to phagocytosis

Answer 113

agglutination

Question 114

small water soluble antigens are settled out of solution and are then engulfed

Answer 114

precipitation

Question 115

antibodies can activate the complement cascade, and release factors which induce the inflammatory response and cell lysis

Answer 115

complement

Question 116

variable regions of the antibody

Answer 116

heavy and light chains

Question 117

regions of the antibody that bind and activate the complement

Answer 117

constant regions

Question 118

what are B cells most effective against

Answer 118

extracellular bacteria, parasites, and viruses

Question 119

B cells respond to invasion by producing antibodies that are specialized globulins known as

Answer 119

immunoglobulins (Ig)

Question 120

antibodies are injected from another source

Answer 120

passive immunity | w

Question 121

individuals will produce their own antibodies

Answer 121

active immunity

Question 122

individual is exposed and develops antibodies and memory cells

Answer 122

active natural immunity

Question 123

* vaccination; antigen is introduced in altered form * memory cells formed

Answer 123

active artificial immunity

Question 124

* passed from mother to newborn through placenta/milk (IgA) * effects wear off in a few months as the child's own immune develops

Answer 124

passive natural immunity

Question 125

* antibodies taken from another source are given via a vaccination * quick fix as body will produce no antibodies naturally

Answer 125

passive artificial immunity

Question 126

steps to fever onset

Answer 126

* hypothalamic thermmostat is reset to higher set point * onset: body temp rises * stadium: body temp oscillates around new set point * infection ends, set point returns to normal * defervescence: body temp returns to normal

Question 127

steps to lymphocyte maturation

Answer 127

1. lymphocytes destined to become T cells migrate (in blood) to the thymus and develop immunocompetence there. b cells develop immunocompetence in red bone marrow 2. immunocompetent but still naive lymphocytes leave the thymus and bone marrow. "seed" the lymph nodes, spleen, and other lymphoid tissues where they encounter their antigen 3. antigen-activated immunocompetent lymphocytes (effector cells and memory cells) circulate continuously in the bloodstream and lymph and throughout the lymphoid organs of the body

Question 128

steps to endogenous protein processing and display

Answer 128

1. endogenous antigen is degraded by protease 2. endogenous antigen peptides enter ER via a transport protein 3. endogenous antigen peptide is loaded onto class I MHC protein 4. loaded MHC protein migrates in vesicle to the plasma membrane, whete it displays the antigenic peptid

Question 129

steps to exogenous protein processing and display

Answer 129

1a. class II MHC synthesized in ER 1b. extracellular antigen is phagocytized 2a. class II MHC is exported from ER in vesicle 2b. phagolysosome degrades antigen 3. vesicle fuses with phagolysosome, invariant chain is removed, and antigen is loaded 4. vesicle with loaded MHC migrates to the plasma membrane

Question 130

MHC II display can cause

Answer 130

costimulation

Question 131

fluid containing clotting factors and antibodies

Answer 131

exudate

Question 132

* a lipid-based chemical messenger synthesized by most tissue cells; acts locally as a paracrine * produced from arachidonic acid

Answer 132

prostaglandins

Question 133

vasodilation of local arterioles cause

Answer 133

local hyperemia

Question 134

increased blood flow due to vasodilation of blood vessels entering the injured area

Answer 134

hyperemia

Question 135

which minerals needed for bacterial reproduction do both the liver and spleen sequester during a fever

Answer 135

iron and zinc

Question 136

when collagen fibers are laid down to a wall of a sac of pus, what structure is formed

Answer 136

abscess

Question 137

mechanism of complement proteins

Answer 137

foorming pores in the membranes of target cells

Question 138

function of neutrophils

Answer 138

phagocytes, will migrate to the site of an infection within a few hours

Question 139

fever inducing molecules are secreted by leukocytes and macrophages

Answer 139

pyrogens

Question 140

which defense cells are common antigen presenting cells (APCs)

Answer 140

macrophages

Question 141

caused by excess tissue fluid in the injured area; helps to dilute harmful substances and brings in excess oxygen

Answer 141

edema

Question 142

nonspecific defense cels specialize in attack cancer cells and virus-infected cells

Answer 142

natural killer cells

Question 143

enzyme in saliva and lacrimal fluids that destroys bacteria

Answer 143

lysozyme

Question 144

a process of coating a pathogen to enhance phagocytosis

Answer 144

opsonization

Question 145

fluid that seeps from the capillary contains clotting factors and antibodies during inflammation

Answer 145

exudate

Question 146

when a localized area exhibits increased capillary filtration, hyperemia, and swelling, it is indication that

Answer 146

inflammation is occurring

Question 147

an increase in the number of white blood cells that are in circulation

Answer 147

leukocytosis

Question 148

process in which neutrophils squeeze through walls of capillaries into the tissues

Answer 148

diapedesis

Question 149

a person may harbor pathogens walled off in ... for years without displaying any symptoms

Answer 149

granulomas

Question 150

first line of defense against pathogens

Answer 150

skin and mucous membranes

Question 151

which of the following is the most specific internal defense against disease a. inflammation b. NK cells c. T cells d. phagocytes

Answer 151

T cells ## Footnote T cells are a part of the adaptive (specific) defenses against disease. They are involved in cell-mediated immunity as they defend the body against specific pathogens.

Question 152

brings more leukocytes to the site of infection

Answer 152

inflammation

Question 152

# true or false: virus-infected cells secrete interferons to "warn" other cells of the presence of virus and these other cells and inhibit viral replication

Answer 152

true

Question 153

role of interferons in defense against disease

Answer 153

protects cells that have not yet been infected by viruses

Question 154

* requires that circulating antibodies are bound to antigens * an example of overlap between innate and adaptive immune function * will result in enhanced inflammation, opsonization as well as formation of MAC proteins

Answer 154

classical activation of complement system

Question 155

* sets the stage for repair processes * prevents the spread of injurious agents to nearby tissue * disposes of cellular debris and pathologies

Answer 155

functions of the inflammatory process

Question 156

redness and heat of an inflamed area are due to local hyperemia caused by

Answer 156

vasodilation

Question 157

unless they are attached to protein carriers, haptens have ... but not ...

Answer 157

reactivity but not immunogenicity

Question 158

how do vaccines work

Answer 158

by priming the adaptive immunity with a relatively harmless primary exposure ## Footnote artificially acquired active immunity

Question 159

results when naive lymphocytes are activated

Answer 159

primary response

Question 160

result of activating memory cells

Answer 160

secondary response

Question 161

A class I MHC protein presents an antigen. What type of cell is likely presenting and to what type of cell would it be presented?

Answer 161

Any nucleated cell would present antigens to a CD8 cell.

Question 162

Which lymphocytes act as the bridge between the cellular and humoral responses?

Answer 162

helper T cells

Question 163

What types of antigen do mature T cells normally not recognize?

Answer 163

self antigens