Brainscape's Knowledge GenomeTM


Top Flashcards (Certified)
All Flashcards

Biology > ch 8 - The Immune System > Flashcards

ch 8 - The Immune System Flashcards

(59 cards)

Start Studying
1
Q

Innate immunity

A

composed of defenses that are always active against infection but lack ability to target specific invaders over others; also called nonspecific immunity. antimicrobial molecules and various phagocytes - some destroy and some trigger more immune cell response

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

adaptive immunity

A

defenses that target a specific pathogen; also called specific immunity; slower to act but can mount a quicker attack in subsequent infections of same pathogen; T-cells which help activate B-cells or other T-cells or directly attack infected cells, and B-cells which secrete antibody molecules that bind to antigens. Both spawn memory cells that kill quicker next time

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

B-cells

A

cell produced in bone marrow, stored and activated in spleen (and lymph nodes). Turn into plasma cells to produce antibodies - adaptive immunity

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

humoral immunity

A

division of adaptive immunity; antibodies dissolve and act in blood rather than within cells

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

T-cells

A

adaptive immune cell produced in bone marrow and matured in thymus; kill virally infected cells

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

cell-mediated immunity

A

T-cells are agents of this because they coordinate the immune system and directly kill virally infected cells

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

lymph nodes

A

major component of the lymphatic system that provides a place for immune cells to communicate and mount an attack; also a site of B-cell activation

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

gut-associated lymphoid tissue (GALT)

A

immune tissue found close to digestive system; includes tonsils, adenoids in head; Peyer’s patches in small intestines; and lymphoid aggregates in the appendix

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

integument

A

skin

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

defensins

A

antibacterial enzymes found in skin

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

complement system

A

consists of proteins in the blood that act as a nonspecific (even though it is associated with antibodies) defense against bacteria by punching holes in them and making them more osmotically unstable

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

classical pathway

A

means of activating complement (system) that requires the binding of an antibody to a pathogen

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

alternative pathway

A

means of activating complement (system) that does not require antibodies

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

interferons

A

proteins produced by cells that have been infected with viruses that prevent viral replication and dispersion; cause nearby cells to decrease production of viral and cellular proteins and decrease permeability of these cells making viral infection more difficult; upregulate MHC (major histocompatibility complex) class I and II molecules resulting in increased antigen presentation and better detection of infected cells by the immune system

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

macrophages

A

type of agranulocyte which resides in tissues; derive from blood-borne monocytes and can beome a resident population in a tissue (more permanent); phagocytizes invader through endocytosis, digests using enzymes and presents pieces to other cells using MHC

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

MHC (major histocompatibility complex)

A

used by macrophages, bind to a pathogenic peptide (antigen) and carries it to the cell surface where it can be recognized by adaptive immune system; come in two main classes (I and II)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

cytokines

A

chemical substances released by macrophages that stimulate inflammation and recruit additional immune cells to the area

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

MHC class I

A

displayed by all nucleated cells in the body; any protein in cell can be loaded onto it and presented on the surface of the cell which allows immune system to monitor the health of these cells and to detect if the cells have been infected. Infected cells would be expected to display a nonself (unfamiliar) protein; called endogenous pathway

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
19
Q

MHC class II

A

displayed only by professional antigen-presenting cells (dendritic cells in skin, macrophages, some B-cells, certain activated epithelial cells)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
20
Q

antigen

A

substance - usually pathogenic protein - that can be targeted by an antibody

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
21
Q

exogenous pathway

A

pathway originating outside the cell such as antigens

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
22
Q

pattern recognition receptors

A

special receptors on macrophages and dendrite cells able to recognize the category of invader (bacterium, virus, fungus, parasite) which allows production of appropriate cytokines to recruit immune cells which target particular groups of pathogens

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
23
Q

Natural killer (NK) cells

A

type of nonspecific lymphocyte able to detect downregulation of MHC and induce apoptosis in virally infected cells; also protect against growth of cancer as cancer also downregulates MHC

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
24
Q

Neutrophils

Study These Flashcards
A

ganulocytes; most populous leukocyte in blood, very short-lived; phagocytic and target bacteria; follow bacteria using chemotaxis (sensing of certain products given off by bacteria) and follow back to bacterium and detect bacteria once they are opsonized (marked with an antibody from a B-cell). dead neutrophils form pus

25
Eosinophils
granulocytes containing bright red-orange granules and are involved in allergic rxns and invasive parasitic infections. release large amounts of histamine (inflammatory mediator) which results in vasodilation and increased leakiness of blood vessels allowing additional immune cells to move out of the bloodstream and into the tissue.
26
basophils
granulocytes containing large purple granules; involved in allergic responses. least populous leukocyte in bloodstream under norm conditions; closely related to mast cells but with smaller granules; exist in tissues, mucosa and epithelium
27
Humoral immunity
form of adaptive immunity; primarily B-cells; involves production of antibodies specific to antigens of the invading microbe; may take up to a week to become fully effective
28
immunoglobulins [Ig]
another term for antibodies; can float freely in blood, chyle (lymph) or air or be present on surface of cell
29
possible functions of antibodies secreted into body fluids
1. bind to specific antigen, attract other leukocytes and phagocitze antigens immediately (osponization), 2. cause pathogens to clump together (agglutinate) forming large insoluble complexes to be phagocytized. 3. block the ability of a pathogen to invade tissues neutralizing it.
30
function of cell-surface antibodies
binding of antigen to a B-cell causes activation of that cell. on surface of mast cell binding causes degranulation (exocytosis of granule contents), allowing release of histamine and causing an inflammatory allergic rxn
31
makeup of antibodies
Y-shaped with heavy chain and light chain held together by disulfide linages and noncovalent interactions. Antigen-binding region at end of variable region (domain) - within which are polypeptide sequences which will bind one specific antigenic sequence - at tips of Y.
32
hypermutation
undergone by B-cells of its antigen-binding region; attempt to find best match for antigen. Also part of the reason it takes so long to initiate the antibody response
33
clonal selection
B-cells that can bind the antigen with high affinity survive and provide a mechanism of generating specificity which is this.
34
constant region (domain) of antibody
remaining part of the antibody other than light chain, joining, V domain, and C domain; the part of the Y between the tips and the stem. this region has receptors for natural killer cells, macrophages, monocytes and eosinophils and it can initiate the complement cascade
35
antibody isotypes
IgM, IgD, IgG, IgE, and IgA
36
isotype switching
process by which cells can change which isotype of antibody they produce when stimulated by specific cytokines
37
on exposure to right antigen b-cells split into these two daughter cells
Plasma cells which produce large amounts of antibodies, and memory B-cells which stay in the lymph node awaiting reexposure to same antigen
38
primary response
initial activation of b-cell antibodies taking about 7-10 days.
39
secondary response
if same microbe is encountered again memory cells produce the antibodies specific to that antigen much more quickly and effectively
40
Positive selection
maturing only cells that can respond to the presentation of antigen on MHC
41
Negative selection
causing apoptosis to cells that are self-reactive (activated by proteins produced by the organism itself)
42
thymosin
peptide hormone secreted by thymic cells that facilitates the maturation of T-cells
43
three major types of T-cells
suppressor T-cells, helper T-cells, and killer (cytoxic) T-cells
44
Helper T-cells (Tsub h)
also called CD4+ T-cells, coordinate the immune response by secreting chemicals (lymphokines) which are capable of recruiting other immune cells (plasma cells, cytoxic T-cells, and macrophages) and increasing their activity. HIV causes loss of these respond to antigens presented on MHC-II molecules
45
Suppresor T-cells (T sub reg)
also called regulatory T-cells; express CD4 like helper T-cells but differentiated because of the expression of protein Foxp3 as well; help to tone down immune response once infection has been contained and turn off self-destructive lymphocytes to prevent autoimmune diseases (termed self-tolerance); most effective against bacterial, fungal and parasitic infections
46
memory T-cells
lie in wait for exposure of antigen again
47
Cytotoxic T-cells (T sub c or CTL)
also called CD8+ c T-cells; directly kill virally infected cells by injecting toxic chemicals that promote apoptosis into the infected cell; respond to antigens presented on MHC-I molecules; most effective against viral and intracellular bacterial or fungal infections
48
Two types of CD4+ T-cells
T sub h 1 which release interferon gamma (IFN-gamma)which activates macrophages and increases their ability to kill bacteria, and T sub h 2 which help activate B-cells and are common in parasitic infections
49
self-antigens
proteins and carbs present on the surface of every cell of the body
50
autoimmunity
occurs when immune system fails to distinguish self and foreign
51
hypersensitivity reactions
immune system misidentifies antigen; allergies and autoimmunity
52
glucocorticoids
modified version of cortisol, used to treat autoimmune diseases because they have potent immunosuppressive qualities
53
active immunity
immune system stimulated to produce antibodies against a specific antigen; vaccines are artificial exposure by this means
54
passive immunity
transfer of antibodies to an individual; transient because only the antibodies and not the plasma cells that produce them are given to the individual
55
thoracic duct
located in posterior chest, allows lymph vessels to join to comprise this which then delivers lymph to left subclavian vein
56
lymph nodes
provide a space for cells of the immune system to be exposed to possible pathogen
57
lacteals
small lymphatic vessels located at center of each villus in small intestine transports fats packaged in chylomicrons by intestinal mucosal cells
58
chyle
lymphatic fluid carrying many chylomicrons which takes on a milky white appearance
59
germinal centers
collections where B-cells proliferate and mature in the lymph nodes

Biology (9 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2025 Bold Learning Solutions. Terms and Conditions