Chapter 43 Key Terms

Question 1

agents that cause disease such as bacteria, viruses, fungi or others

Answer 1

pathogens

Question 2

system that enables animals to avoid or limit many infections

Answer 2

immune system

Question 3

two types of molecular recognition

Answer 3

innate immunity and adaptive immunity

Question 4

a defense active immediately upon infection

Answer 4

innate immunity

Question 5

a response activated after the innate response and develops more slowly

Answer 5

adaptive immunity

Question 6

what kind of immunity are barrier defenses?

Answer 6

innate

Question 7

enzyme that breaks down bacterial cell walls (defense of invertebrates)

Answer 7

lysozyme

Question 8

major immune cells of insects

Answer 8

hemocytes

Question 9

process of cells breaking down microorganisms

Answer 9

phagocytosis

Question 10

transmembrane receptor activated by binding of recognition proteins to fungal cell wall molecules (invertebrates)

Answer 10

Toll

Question 11

activate production and secretion of antimicrobial peptides that kill fungal cells (invertebrates)

Answer 11

Toll

Question 12

innate defenses of vertebrates similar to invertebrates

Answer 12

barrier defenses, phagocytosis, and antimicrobial peptides

Question 13

innate defenses unique to vertebrates

Answer 13

natural killer cells, interferons, inflammatory response

Question 14

barrier defenses include:

Answer 14

skin and mucous membranes

Question 15

how does the skin and digestive system defend against the growth of bacteria

Answer 15

low pH of skin

Question 16

innate immune cells in mammals detect, devour, and destroy invading pathogens using ___________ to recognize groups of pathogens

Answer 16

TLRs (toll like receptors)

Question 17

recognize fragments of molecules characteristic of a set of pathogens

Answer 17

toll like receptors (TLR)

Question 18

two MAIN kinds of phagocytic cells

Answer 18

neutrophils and macrophages

Question 19

engulf and destroy pathogens

Answer 19

phagocytic cells

Question 20

phagocytic cells that circulate in the blood

Answer 20

neutrophils

Question 21

phagocytic cells that migrate through the body or reside permanently in organs and tissues

Answer 21

macrophages

Question 22

two ADDITIONAL types of phagocytic cells

Answer 22

dendritic cells and eosinophils

Question 23

phagocytic cells that stimulate development of adaptive immunity

Answer 23

dendritic cells

Question 24

phagocytic cells that discharge destructive enzymes against parasites

Answer 24

eosinophils

Question 25

type of innate defense; these circulate the body and detect abnormal cells; release chemicals leading to cell death, inhibiting the spread of virally infected or cancerous cells

Answer 25

natural killer cells

Question 26

immune cells found in connective tissue; discharge cytokines (part of inflammatory response)

Answer 26

mast cells

Question 27

signaling molecules that recruit neutrophils to an inflamed site

Answer 27

cytokines

Question 28

chemical that triggers blood vessels to dilate and become more permeable

Answer 28

histamine

Question 29

__________migrate to lymph nodes after interacting with pathogens to stimulate adaptive immunity

Answer 29

dendritic cells

Question 30

proteins that provide innate defense by inhibiting the replication of viruses

Answer 30

interferons

Question 31

system that consists of about 30 proteins in blood plasma; activated by substances on the surface of many pathogens; resulting cascade of reactions lead to lysis of invading cells

Answer 31

complement system

Question 32

adaptive response relies on 2 types of lymphocytes:

Answer 32

T cells and B cells

Question 33

lymphocytes that mature in the thymus

Answer 33

t cells

Question 34

lymphocytes that mature in bone marrow

Answer 34

b cells

Question 35

lymphocytes are?

Answer 35

a type of white blood cell

Question 36

substances that can elicit a response from b or t cells

Answer 36

antigens

Question 37

t or b cells bind to antigens via ____________ specific to part of one molecule of that pathogen

Answer 37

antigen receptors

Question 38

small accessible part of an antigen that binds to an antigen receptor

Answer 38

epitope

Question 39

soluble form of the receptor

Answer 39

antibody or immunoglobulin (Ig)

Question 40

__________bind only to antigen fragments displayed or presented on a host cell

Answer 40

T cells

Question 41

cell surface proteins that antigen fragments are bound to, the antigen fragment bound to T cells

Answer 41

Major histocompatibility complex molecules (MHC)

Question 42

a process in which MHC molecules bind and transport antigen fragments to the cell surface

Answer 42

antigen presentation

Question 43

the ________ immune system has 4 major characteristics: - immense diversity of lymphocytes and receptors - self tolerance: lack of reactivity against an animal's own molecules and cells - B and T cells proliferate after activation - immunological memory

Answer 43

adaptive

Question 44

light chain (in b and t cells) is encoded by 3 segments:

Answer 44

V (variable), J (joining), and (c) constant

Question 45

enzyme that acts randomly to connect different V and J segments in each B cell

Answer 45

recombinase

Question 46

multiple cell divisions that a B or T cell undergoes to produce a clone of identical cells

Answer 46

clonal selection

Question 47

cells from the clone that act immediately against the antigen; plasma cells that secrete antibodies

Answer 47

effector cells

Question 48

remaining cells in the clone; long lived and can give rise to effector cells if the same antigen is encountered again

Answer 48

memory cells

Question 49

responsible for long term protection against diseases

Answer 49

immunological memory

Question 50

first exposure to a specific antigen represents the

Answer 50

primary immune response

Question 51

when memory cells facilitate a faster, greater and more prolonged response from a reservoir of T and B memory cells

Answer 51

secondary immune response

Question 52

two kinds of defenses provided by B and T lymphocytes

Answer 52

humoral immune response and cell-mediated immune response

Question 53

antibodies help neutralize or eliminate toxins and pathogens in the blood and lymph

Answer 53

humoral immune response

Question 54

specialized T cells destroy infected host cells

Answer 54

cell mediated immune response

Question 55

what kind of cell activates both the humoral and cell mediated immune response

Answer 55

helper t cell

Question 56

antibodies bind to antigens on bacteria promoting phagocytosis (marking them)

Answer 56

opsonization

Question 57

cells that use toxic proteins to kill cells infected by viruses or other intracellular pathogens

Answer 57

cytoxic t cells (killer t cells)

Question 58

protection provided by a second immune response provides the basis for immunization

Answer 58

immunization

Question 59

develops naturally when a pathogen invades the body and elicits a primary or secondary immune response

Answer 59

active immunity

Question 60

provides immediate, short term protection

Answer 60

passive immunity

Question 61

life threatening reaction to allergen

Answer 61

anaphylactic shock

Question 62

the immune system loses tolerance for self and turns against certain molecules of the body

Answer 62

autoimmune diseases

Question 63

some pathogens can change epitope expression and prevent recognition by the host

Answer 63

antigenic variation

Question 64

inactive state of virus

Answer 64

latency