IMMUNE SYSTEM LECTURE Flashcards
1
Q
Describe an innate or “non-specific” immune defense system?
A
an innate defense system is broadly effective and has no prior exposure to the pathogen
2
Q
What are examples of pathogens that your innate immune defense system may be exposed to?
A
some examples of pathogens are toxins and living organisms
3
Q
What are the first lines of defense regarding the immune system?
A
the skin and mucous membrane are the first line of immune defense
4
Q
A
5
Q
Describe why the skin is effective in deterring pathogens.
A
the skin is effective because it is difficult to penetrate, dry, nutrient poor, and coated with antimicrobial chemicals such as defensins and a thin layer of lactic acid
6
Q
What makes the skin difficult for pathogens to penetrate?
A
the skin is difficult to penetrate due to its keratin (protein)
7
Q
Describe why the mucous membrane is effective in deterring pathogens.
A
the mucous membrane is effective due to the stickiness of the mucous traps and the lysosomes it contains
8
Q
Where can the defensive mucous membrane be located?
A
mucous membranes line all of the body cavities that open to the exterior of the
9
Q
What are examples of body cavities that open to the exterior?
A
examples of body cavities that open to the exterior are the digestive, respiratory, urinary, and reproductive systems tracts
10
Q
What is the function of the stickiness of the mucous membrane traps within the immune defense system?
A
the stickiness of the mucous membrane traps harmful organisms
11
Q
What is the function of the lysosomes in the defensive mucous membranes?
A
the lysosomes are enzymes that are responsible for destroying bacteria cell walls
12
Q
What is the function of internal immune defenses?
A
internal immune defenses are responsible for targeting organisms that penetrate the skin/ mucous membrane barrier
13
Q
What is the second line of immune system defense?
A
the second line of the immune system defense is the internal defenses
14
Q
What are phagocytes?
A
phagocytes are white blood cells
15
Q
What are some examples of phagocytes?
A
some examples of phagocytes are neutrophils, macrophages, and monocytes
16
Q
Define phagocytosis.
A
phagocytosis is when phagocytes must attach to a pathogen in order to consume it
17
Q
What do phagocytes use in order to be able to attach to a pathogen?
A
phagocytes use cytoplasmic extension in order to attach to pathogens
17
Q
Describe the function of a pathogens carbohydrate signature.
A
a pathogens carbohydrate signature allows white blood cells to detect and connect to the pathogen
18
Q
Describe the function of external capsules.
A
external capsules allow some bacteria to conceal their carb signatures
19
Q
Why is it significant that some pathogens use external capsules to cover their carb signatures?
A
pathogens using external capsules to cover their carb signatures because it prevents phagocytes from grabbing on to the pathogen; phagocyte is unable to destroy pathogen
20
Q
Describe the function of opsonins.
A
opsosnins coat the external capsules and provide “handles” for phagocytes to bind to
21
Q
What are opsonins?
A
opsonins are complement proteins/ antibodies
22
Q
Define opsonization.
A
is the process of phagocytes using opsonins to bind to the external capsules of pathogens
23
Q
Define respiratory burst?
A
respiratory burst is when…
24
What is the function of natural killer (nk) cells?
natural killer cells are responsible for attacking and killing cancer and virus infected cells, bacteria, or cell transplanted tissues
25
What happens when a natural killer cell recognizes an abnormal cell?
when a natural killer recognizes an abnormal cell it secretes proteins which bind to the pathogen
26
What is the function of the chemicals that natural killer cells secrete?
the chemicals that natural killer cells secrete increase the inflammatory response
27
What are the two types of immunity?
the two types of immunity are cellular immunity and humoral immunity
28
Humoral immunity is also known as what?
humoral immunity is also known as "antibody-mediated" immunity
29
Cellular immunity is also known as what?
cellular immunity is also known as "cell-mediated" immunity
30
Describe what happens in a cellular (cell-mediated) immune response.
in a cellular immune response lymphocytes either directly attack diseased/ "suspicious" cells or indirectly activate other lymphocyte or macrophages with a chemical response
31
Describe what happens in a humoral (antibody-mediated) immune response.
in a humoral immune response circulating antibodies in bodily fluids bind to bacteria/ toxins/ viruses and inactivate or "tag" them for destruction
32
What produces the antibodies within the humoral immune system?
antibodies within the humoral immune system are produces by lymphocytes
33
How are bacteria/ toxins/ viruses inactivated or "tagged" within the humoral (antibody-mediated) immune system?
lymphocytes in the bodily fluids inactivate or "tag" bacteria/ toxins/ viruses by using phagocytes and complement
34
Describe the anatomical structure of antigens.
antigens are large, complex molecules
35
What are three different types of antigens?
three different types of antigens are proteins, polysaccharides, and glycoproteins
36
Describe the relationship between antigens and an immune response.
antigens are not normally present in the body but are responsible for triggering an immune response
37
What are the two functional properties of complete antigens?
the two functional properties of complete antigens are immunogenicity and reactivity
38
Define immunogenicity in reference to complete antigens.
immunogenicity is the ability to cause specific lymphocytes to multiply
39
Define reactivity in reference to complete antigens.
reactivity is the ability to react with the activated lymphocytes and antibodies
40
What is another term for incomplete antigens?
incomplete antigens are also termed "haptens"
41
What is the result of incomplete antigens (haptens)?
the result of incomplete antigens is a hypersensitivity to antibodies
42
What are the characteristics of incomplete antigens (haptens)?
incomplete antigens are small molecules
43
True or False: incomplete antigens are immunogenic.
false; incomplete antigens are not immunogenic
44
Describe what happens if an incomplete antigen links with the body's own proteins.
if an incomplete antigen links with the bodies own protein the adaptive immune system will attack it causing more harm than good
45
What are some examples of the immune response of an incomplete antigen?
some examples of reactions like this are reactions to penicillin, poison ivy, animal dander, some detergents, and some cosmetics
46
Define what antigen determinants are.
antigen determinants are binding sites for antibodies or lymphocytes on antigen surfaces that stimulate an immune response
47
What are "self-antigens"?
"self antigens" are surface glycoproteins that mark cells as "self" for the immune system
48
What is the purpose of "self-antigens"?
"self-antigens" prevent the immune system from attacking it's own cells
49
What are the glycoproteins within that are used in "self-antigens" called?
"self-antigens" use glycoproteins called major histocompatibility complexes
50
Where do (t) lymphocytes originate from?
(t) cells originate from stem cells in the bones marrow
51
Where do (t) lymphocytes develop?
(t) lymphocytes develop in the thymus
52
What is the function of (t) cells?
(t) cells provide cellular immunity
52
Where do (b) lymphocytes originate from?
(b) cells originate from stem cells in the bone marrow
53
Where do (b) cells develop?
(b) lymphocytes develop in the bones marrow
54
What is the function of (b) cells?
(b) cells release antibodies that provide humoral immunity
55
What is the function of antigen-presenting cells (APCs)?
antigen-presenting cells are responsible for internalizing antigens and presenting them to antigenic determinants on their surfaces for (t) cell recognition
56
Why are antigen-presenting cells important?
without antigen-presenting cells, (t) cells could not recognize which pathogens to eliminate
57
Describe the function/ structure of dendritic cells.
dendritic cells are also responsible for catching antigens due to their long wispy extensions
58
What level of (t) lymphocytes do dendritic cells present antigenic determinants to?
dendritic cells present antigenic determinants to (t) cells while they are in the lymph node
59
True or False: when macrophages present antigenic determinants to naive (t) cells, both can be activated.
true; when macrophages present antigen determinants to naive (t) cells both are activated
60
What happens to macrophages that are activated while presenting antigen determinants to naive (t) cells?
macrophages that are activated while presenting antigen determinants can become "killer" macrophages
61
What level of (t) lymphocytes do (b) lymphocytes present antigen-determinants to?
(b) lymphocytes present antigen determinants to "helper" lymphocytes
62
What is the purpose of (b) cells presenting antigen determinants to (t) cells?
(b) cells present antigen determinants to (t) cells in order to initiate their own activation
63
How long does it take both (t) and (b) lymphocytes to mature?
it take 2-3 days for both (t) and (b) lymphocytes to mature
64
Where do both (t) and (b) lymphocytes originate?
both (t) and (b) lymphocytes originate in the red bone marrow
65
Define immunocompetence in reference to (t) and (b) lymphocytes.
immunocompetence is the ability of a lymphocyte to recognize its specific antigen by using a unique type of receptor on their surface
66
Define self-tolerance in reference to (t) and (b) lymphocytes.
self-tolerance is the ability for a lymphocyte to be unresponsive to the bodies self-antigens
67
What is the importance of "self-tolerance"?
"self-tolerance" prevents the body from attacking its own cells
68
Where are naive (t) and (b) cells taken to gain exposure to antigens?
(t) and (b) calls are taken to the lymph nodes, spleen, etc. to gain exposure to antigens
69
Define clonal selection in reference to (t) and (b) cells.
clonal selection is when antigens bind to receptors on a specific lymphocyte
70
How many receptor per lymphocyte are there?
there are ~100,000 receptors/ per lymphocyte
71
Once activated, lymphocytes proliferate to form what?
once activated lymphocytes proliferate in order to form and "army" of clones
72
What are effector cells?
effector cells are clones that do the fighting
73
What are two types of effector cells?
two types of effector cells are (t) cells and (b) cells
74
What is the responsibility of (t) cells as an effector cell?
(t) cells are responsible for fighting off antigens
75
What is the responsibility of (b) cells as an effector cell?
(b) cells are responsible for releasing antibodies
76
What are memory cells?
memory cells are long-living clones of effector cells that respond immediately pathogens and produce more cells
77
Most (b) cell clones differentiate into what?
most (b) cell clones differentiate into plasma cells
78
What are plasma cells?
plasma cells are antibody secreting effector cells
79
Plasma cells secrete antibodies at what rate?
plasma cells secrete ~2000 antibodies/ second for 4-5 days
80
What happens to plasma cells after 4-5 days?
they stop secreting antibodies and die
81
What happens to the antibodies secreted by plasma cells?
antibodies secreted by plasma cells circulate the blood and lymph in order to bind to antigens and mark them for destruction
82
Define a primary immune response.
a primary immune response is the cellular proliferation/ differentiation that occurs in the first exposure to an antigen
83
How long does it take a primary immune response to occur?
a primary immune response typically takes 3-6 days after the antigen is discovered to occur
84
How long does it take for the antibody levels to reach its peak during a primary immune response?
it takes ~10 days for the antibody levels to reach its peak before it declines
85
Define a secondary immune response.
a secondary immune response is a re-exposure to an antigen that results in a faster, longer, and more effective response
86
Which cells contribute to making the secondary immune response much faster than the primary immune response?
the secondary immune response is much faster than the primary immune response due to memory cells
87
How long does it take for antibody levels to reach its peak during a secondary immune response?
it takes 2-3 days for antibody levels to reach its peak during a secondary immune response
88
True or False: a secondary immune response produces fewer plasma cells than a primary immune response.
false; a secondary immune response produces more plasma cells than an immune response
89
How long to antibody levels remain high after a secondary immune response?
antibody levels in the body can remain high for weeks/ months
90
Define naturally-acquired active immunity.
naturally-acquired active immunity is the production of one's own antibodies or (t) cells as a result of a prior infection
91
True or False: a naturally-acquired active immunity produces memory cells
true; a naturally acquired active immunity produces memory cells
92
Define an artificially-acquired active immunity.
an artificially acquired active immunity is the production of one's own antibodies/ (t) cells as a result of a vaccination
93
True or False: an artificially-acquired active immunity produces memory cells
true; an artificially-acquired active immunity produces memory cells
94
Describe to content of vaccines.
most vaccines contain dead or weakened pathogens
95
What is a result of a vaccine composed of pathogens that aren't weakened enough?
a vaccine composed of pathogens that aren't weakened enough may result in disease
96
Define a naturally-acquired passive immunity.
a naturally-acquired passive immunity is when a fetus acquires temporary antibodies; immunity is borrowed
97
Where does the fetus receive naturally-acquired passive immunity from?
the fetus receives naturally-acquired passive immunity from the mother during breast milk/ placenta
98
What is the immune defense benefit of breast feeding infants?
breast fed infants are protected from all antigens that the mother was exposed to
99
Define an artificially-acquired passive immunity.
an artificially acquired passive immunity is the injection of immune serum obtained from another individual or animal that has produced antibodies against an antigen; a mortality preventative vaccine
100
What is the rationale behind receiving artificially-acquired passive immunity?
an individual would typically receive artificially-acquired passive immunity vaccines against diseases that would rapidly kill them in any other instance
101
What are some examples of rapid approaching/ deadly diseases?
some examples of rapidly approaching/ deadly diseases are hepatitis, poison snake bites, rabies, and tetanus
102
What is another term for antibodies?
another term for antibodies is "immunoglobins" (igs)
103
What are immunoglobins (antibodies)?
immunoglobins are proteins produced by antigen-stimulated effector (b) plasma cells that prey on extracellular pathogens
104
What is the anatomical structure of immunoglobins (antibodies)?
immunoglobins are made up of four looing polypeptide chains linked together by disulfide bonds
105
Describe the heavy; light ratio in the polypeptide chain of an immunoglobin.
the four polypeptide chains have 2 heavy; 2 light polypeptide chains
106
What are the five classes of immunoglobins?
the five classes of immunoglobins are: IgM, IgA, IgD, IgG, and IgE
107
Which class of immunoglobins is most abundant?
IgG is the most abundant immunoglobin class
108
Describe the IgG immunoglobin class.
the IgG immunoglobin class is the most abundant/ diverse antibody in a primary and secondary response
109
True or False: the IgG crosses the placenta and enables passive immunity
true; the IgG crosses the placenta and enables passive immunity
110
Describe what occurs during neutralization.
during neutralization an antibody blocks binding sites of viruses/ bacteria to prevent them from binding to tissue
111
Describe what occurs during agglutination.
during agglutination an antibody uses multiple binding sites and clump things together
112
Describe what occurs during precipitation.
during precipitation soluble molecules clump making it easier to clear the via phagocytosis
113
Define the term "complement".
complement is the primary antibody defense against cellular antigens
114
Describe what occurs during complement.
during complement several antibodies bind close together on the same cell resulting in cell lysis
115
How many tests must a developing (t) lymphocyte pass in order to survive?
the (t) lymphocytes must pass two tests
116
What percentage of (t) cells fail the developmental tests?
98% of (t) lymphocytes fail their tests
117
Define "positive selection".
"positive selection" is where only (t) cells that are able to recognize and bind to "self" made cells
118
What is the first test that (t) lymphocytes must go though?
the first test that (t) cells must go through is positive selection
119
What is the second test that (t) lymphocytes must go through?
the second test that (t) lymphocytes must go though is negative selection
120
Define "negative selection".
"negative selection" is where (t) cells must not bind to any self-antigens that are presented within the (mhc) molecule
121
Define "self tolerance".
"self tolerance" is the destruction of a (t) lymphocyte if they attack self-made antigens
122
What are the two major differentiation glycoproteins on a cells surface?
the two major glycoproteins on a cells surface are CD4 and CD8
123
How are the two major populations of (t) cells defined?
the two major populations of cells are defined by differentiation glycoproteins on a cells surface
124
Describe what occurs when CD4 cells are activated.
When CD4 cells are activated they typically become helper (t) cells
125
What is the function of helper (t) cells/ CD4 cells?
when activated, helper (t) cells activate (b) cells, other (t) cells, macrophages, and direct the adaptive immune response
126
As opposed to becoming helper (t) cells some CD4 cells become what?
some CD4 cells become regulatory (t) cells
127
What is the responsibility of regulatory (t) cells?
regulatory (t) cells are responsible for moderating the immune system
128
What is another term for regulatory (t) cells?
another term for regulatory (t) cells are "suppressor cells"
129
Describe what occurs when CD8 cells are activated.
when activated CD8 cells become cytotoxic and directly destroy pathogens
130
True or False: both CD4 cells and CD8 cells can become memory cells.
true; both CD4 cells and CD8 cells can become memory cells
131
Where can class I MHC proteins be found?
class I (mhc) proteins can be found on the cell membrane of all nucleated body cells and (apcs)
132
What are some examples of APCs that contain class I MHC proteins?
some examples of (apcs) that contain class I MHC proteins are dendritic cells, macrophages, and (b) cells
133
Which antigen do class I MHC proteins contain?
class I MHC proteins contain endogenous antigens
134
Which type of endogenous antigen do class I MHC proteins contain?
class I MHC proteins contain protein 8-9 AA long
135
True or False: in healthy cells the antigens are self antigens
true; in healthy cells the antigens are self antigens
136
True or False: in infected cells the antigen does not contain pieces that belong to the pathogen
false; in an infected cell the antigen contains pieces that belong to the pathogen
137
Where can class II MHC proteins be found?
class II (mhc) proteins can be found only in (apcs)
138
True or False: class II MHC proteins contain an exogenous antigen
true; class II (mhc) proteins contain an exogenous antigen
139
what is the exogenous protein that class II MHC proteins contain?
class II (mhc) proteins contain protein 14-17 AA long
140
Where does the protein 14-17 AA long come from?
the protein 14-17 AA long comes from outside the cell (pathogen) that was engulfed
141
What happens once the engulfed antigen is displayed on an APCs surface?
once displayed on the (apcs) surface the antigen is recognized by CD4 cels signaling that help is needed
142
What is the purpose of APCs cells displaying pathogens on their surface/
the (apc) cells display pathogens on their surface in order to show CD4 cells what to attack
143
How many steps does it take for a (t) cells to be activated by an APC?
it takes two steps for a (t) cell to be activated by an (apc)
144
Describe the first step of (t) cell activation by an APC?
the first step of (t) cell activation is that the (t) cell antigen receptor (trc) binds to an antigen (mhc) complex on the suface of the (apc)
145
Describe the second step of (t) cell activation by an APC?
the second step of (t) cell activation is that the (t) cell must also bind to co-stimulatory molecules on the surface of the (apc)
146
What happens to the co-stimulatory molecules when defenses are mobilized?
the co-stimulatory molecules begin to "sprout" to the cell surface when innate defenses are being mobilized
147
Why is it important that (t) cells also bind to co-stimulatory molecules on a cells surface?
(t) cells also binding to co-stimulatory molecules is important to ensure that (t) cells do not attack healthy cells
148
Describe what happens to a (t) cell once activated by antigen binding and co-stimulation.
once activated by antigen binding and co-stimulation a (t) cell enlarges and proliferates
149
What happens when a (t) cells proliferates after being activated?
when a (t) cell proliferates after being activate it forms clones under the direction of cytokines
150
Define cytokines.
cytokines is a chemical messenger
151
What are two examples of cytokines?
two examples of cytokines are interferons and interleukins
152
What is the timeframe of a response peak after (t) cell activation?
response peaks after a weak of exposure to the triggering antigen
153
What is the timeframe of apoptosis?
apoptosis occurs between 7-30 days as the antigen levels drop
154
How long do memory cells last after an exposure?
memory cells remain indefinitely after an exposure
155
What is the function of helper (t) cells "coaches"?
once activated by (apc) they use cytokines to activate (t) and (b) cells and induce them to proliferate
156
What is the function of cytotoxic (t) cells "players"?
cytotoxic (t) cells are the only cells that can directly attack other cells
157
True or False: cytotoxic (t) cells hide until an infection occurs?
false; cytotoxic (t) cells roam the blood/ lymph/ and lymphoid tissue searching for body cells displaying antigens they recognize
158
What are the main targets of cytotoxic (t) cells?
the main targets of cytotoxic (t) cells are viral infected cells, cancer cells, bacteria, parasites, and any other foreign cells
159
Describe the methods of destruction for cytotoxic (t) cells.
cytotoxic (t) cells use perforins or bind to membrane receptors that cause its target to undergo apoptosis
160
What is apoptosis?
apoptosis is programmed cell death; cell suicide
161
Which two cells examine other cells for markers they might recognize?
both natural killer cells and cytotoxic (t) cells examine other cells for markers they might recognize
162
Describe the difference between natural killer cells and cytotoxic (t) cells.
natural killer cells check proteins; cytotoxic (t) cells check superficial flags to make sure the cell looks normal
163
