Brainscape's Knowledge GenomeTM

Browse over 1 million classes created by top students, professors, publishers, and experts.


See full index

Microbiology and Parasitology > Immunology 2 > Flashcards

Immunology 2 Flashcards

1
Q

Involves a third line of defense
Slower response but has a memory component
Involves Lymphocytes and Antibodies

A

Adaptive Immmunity

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

Different types of adaptive immunity

A

Naturally Acquired Active Immunity
Naturally Acquired Passive Immunity
Artificially Acquired Active Immunity
Artificially Acquired Passive Immunity

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

Type of adaptive immunity where antigens enter the body and produces Ab and specialized lymphocytes (Infections)

A

Naturally Acquired Active Immunity

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

Type of adaptive immunity where vaccination or immunization are administered

A

Artificially Acquired Active Immunity

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

Type of adaptive immunity where preformed Ab are given

A

Artificially Acquired Passive Immunity

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

Type of immunity carried out by antibodies circulating in the blood in response against a specific epitope and provide defense against extracellular microbes

A

Humoral immunity

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

In every 10 trillion B cells, there are

A

100M distinct Ab

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

Any molecule (either proteins or polysaccharides) that can bind specifically to generate antibodies

A

Antigen

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

Antigen that can elicit Ab production

A

Immunogens

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

Usually antigenic when combined with proteins and polysaccharides

A

Lipids and nucleic acids

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

Chemical basis of Ag resides in their macromolecular composition

A 
Carbohydrates
Glycoproteins
Proteins
Lipids
Lipoproteins
Nucleic acid
Nucleoproteins
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

Most antigenic composition of antigens

A

Proteins

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

Least antigenic composition of antigens

A

Nucleic acids

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

Antigenic determinant and regions on Ag which an Ab recognize

A

Epitopes

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

Site on Ab that binds to the epitope

A

Paratopes

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

Unique set of antigenic determinants on the variable portion of an Ab

A

Idiotypes

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

Antigens that do not elicit elicit antibody production by themselves

A

Haptens

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

Chracteristics of haptens

A 
Small molecules (with low MW: < 10,000)
Act as Ag if bind to bigger molecules
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
19
Q

Example of a hapten

A

Penicillin (hapten) when bound to host serum proteins, it can initiate an immune response

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

True or False.

Antigenicity is related to MOLECULAR WEIGHT.

A

True.

Very large molecules (10,000 Dalton to 600,000 Da) = highly antigenic
Low molecular weight molecules (< 5000 Da) - non-antigenic

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

“anti-antigens”

Class of proteins called immunoglobulins (Ig) found in blood serum, body fluids, tissues

A

Antibodies

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

Produced in response to a particular epitope on the surface of pathogen
Helps other cells or molecule inactivate or destroy the infectious agent or their products

A

Antibodies

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

Characteristics of antibodies

A

Highly specific

Soluble

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

Antibody structure

A 
4 polypeptide chains (2 light chains and 2 heavy chains)
Disulfide bond
Variable region (antigen-binding site)
Constant region
Fab (Fragment antigen binding)
Fc (Fragment crystallizable)
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
25
Q

Antigen binding fragment
Recognizes antigen
Attaches to disease agent’s epitopes

A

Fab

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
26
Q

Mediates binding of Ig to host tissues, thus mediating biologic activity of the Ig molecule → constant regions heavy chains: alpha (IgA), gamma (IgG), mu (IgM), delta (IgD), and epsilon (IgE)

A

Fc

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
27
Q

Classes of Ab

A 
IgG
IgM
IgA
IgD
IgE
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
28
Q

Characteristics of IgG

A

80% of serum Ig; 20% of all plasma protein

Only Fc region recognized by phagocytes and NK cells

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
29
Q

Characteristics of IgM

A

5-10% of Ig in normal human serum
Located in serum and B cell membrane
Predominant Ab involved in response to the ABO blood group Ag on the surface of RBCs
Aids in phagocytosis
With minor role in inhibiting microbial adhesion

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
30
Q

Characteristics of IgA

A

Accounts for 10-15% of total Ig
Small amounts in blood serum
Usually secreted across mucosal surfaces (respiratory, GIT, gut)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
31
Q

Characteristics of IgD

A

Found in serum
< 0.2% of the total serum Ab
Less than 10% of fetal Ig
Found in blood, lymph, and surface of B cells
Act as Ag receptors on surfaces of B cells
No well defined function in serum

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
32
Q

Characteristics of IgE

A

Very low concentration in serum (0.002%)
Monomer
Found mainly in body fluids, beneath the skin and mucosa
Fc has special affinity for receptors on plasma membrane of basophils in blood and mast cells in tissues (specialized cells that participate in allergic reactions)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
33
Q

Main class of Ab

A

IgG

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
34
Q

Monomer-shaped Ab

A

IgG, IgD, IgE

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
35
Q

Ab that can cross the placenta

A

IgG

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
36
Q

Ab that can activate the complement

A

IgG

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
37
Q

First Ig produced in an immune response, but short-lived

A

IgM

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
38
Q

Shape of IgM in secretion

A

Pentamer: 5Y shaped units connected by Fc region to J chain

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
39
Q

Shape of IgM in plasma

A

Monomer: Single Y shape IgM forms part of B cell plasma membrane

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
40
Q

First Ig formed in fetus

A

IgM

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
41
Q

Most abundant Ab in the body

Secretory Ab: main Ig in external body secretions (mucus, tears, saliva, breast milk - colostrum, urine)

A

IgA

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
42
Q

Function of IgA

A

Prevent attachment of microbial pathogen to mucosal surface

IgA immunity is relatively shorter-lived

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
43
Q

Shape of IgA in serum

A

Monomer

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
44
Q

Shape of IgA in mucous membrane

A

Dimer

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
45
Q

Concentrated along with IgM on plasma membrane of human B lymphocyte

A

IgD

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
46
Q

Called reagin

47
Q

Functions of IgE

A

Antigen → cross links with IgE + basophil/mast cell → release of Histamine or chemical mediators → allergic response
Attract complement and phagocytic cells
Key role in combating helminths
With damaging role in development of allergies such as drugs, pollens, and certain food

48
Q

These are B cells in the resting stage
Produce IgM and IgD on their surface
If binds to antigen: activation is initiated

A

Naive B cells

49
Q

When infection is over plasma cells die and memory cells continue to circulate

A

Immunological memory

50
Q

Ability of the immune system to quickly and recognize an Ag that the body has previously encountered and initiate a corresponding immune response

A

Immunological memory

51
Q

Primary or Secondary immune response.

First time to encounter Ag

52
Q

Primary or Secondary immune response.

Anamnestic response

53
Q

Primary or Secondary immune response.

Initiated by virgin B cells

54
Q

Primary or Secondary immune response.

Initiated by memory B cells

55
Q

Primary or Secondary immune response.

Takes 1-2 weeks to develop fully

56
Q

Primary or Secondary immune response.

Produce Ab more rapidly in a few days because it recognizes the microbe already

57
Q

Primary or Secondary immune response.

Generate more Ab due to memory cells`

58
Q

Primary or Secondary immune response.

IgM is the first Ig produced

59
Q

Functions of antibodies in host defense

A 
Neutralization
Opsonization
Agglutination
Inflammation
Antibody-dependent cell cytotoxicity (ADCC)
Complement system activation
60
Q

Inactivate toxins or vital compounds on surface of pathogens by binding on them

A

Neutralization

61
Q

Mechanisms of neutralization

A
  1. Some Ab (antitoxins) → binds to toxins (Ag) → Inactivates toxins
  2. Ab → bind to Ag (responsible for attachment to host cell) → Virus can’t attach to host cell → Infection prevented
62
Q

Ab bind to Ag on surface of pathogens facilitating destruction by phagocytes

A

Opsonization

63
Q

Ab cause Ag to agglutinate

Binds microbes together and then eliminate it through phagocytosis

A

Agglutination

64
Q

When cells/microorganisms are destroyed this attracts phagocytes to the area therefore increasing neutrophils leading to inflammation

A

Inflammation

65
Q

Mechanism of inflammation

A

Cells/Microbes are destroyed → Attracts phagocytes → Increase Neutrophils → Inflammation

66
Q

Leads to cytolysis, inflammation, and phagocytosis

A

Complement system activation

67
Q

Major biologic effects of complement system

A
  1. Opsonization
  2. Chemotaxis
  3. Anaphylatoxins
  4. Cytolysis
68
Q

Ab-Ag complexes easily phagocytosed in the presence of C3b (many C3b Rc on phagocytes)
C3b enhances phagocytosis

A

Opsonization

69
Q

Movement of leukocytes to site of infection

Neutrophil and monocyte movement stimulated by C5a

A

Chemotaxis

70
Q

C3a and C5a (potent anaphylatoxins) binds to mast cells causing degranulation of mast cells
Releases histamine causing vasodilation, increased vascular permeability and muscle contraction.

A

Anaphylatoxins

71
Q

Lysis of cells (RBC, bacteria, tumor cells) due to the development of membrane attack complex (C5b6789)

72
Q

Type of immunity that provide defense against intracellular microbes and can control intracellular infections that Ab cannot reach

A

Cell-medicated immunity

73
Q

Immunity that is mediated by T lymphocytes

A

Cell-mediated immunity

74
Q

Recognize antigens produced by intracellular microbes
Usually occurs when the antigens are embedded in the cell membrane or inside the host cells
Therefore, inaccessible to antibodies

A

Cell-mediated immunity

75
Q

True or False.

T cells with membrane receptors for antigens provide defense against intracellular microbes.

76
Q

Cell-mediated immunity is effective in:

A

Clearing the body of virus-infected cells

Defending the body against fungi, helminths, cancer, and foreign tissue (transplanted organs)

77
Q

Phenomenon when T cells in the resting state bind the antigen fragment on MHC or on APC to stimulate T cell to divide & secrete lymphokines. This sets the immune response into motion.

A

T-cell activation

78
Q

True or False.

T-cell activation stimulates itself by producing IL-2 which combines with Ag causing it to multiply.

79
Q

recognition molecule for T cells

A

TCR complex

80
Q

2 classes of TCR

A

a-B (more common)

y-D

81
Q

True or False.

Similar to Fab regions of Ig, it has variable and constant regions. Variable region binds the peptide-MHC complex.

82
Q

True or False.

T cell signal is also enhanced by coreceptors, CD4 and CD8 molecules CD4 binds to MCH II and CD8 binds to MHC I.

83
Q

Mechanism of cell-mediated immunity

A
  1. A macrophage inserts an antigen or a peptide fragment on the MHC of the macrophage.
  2. The T helper cell recognizes the peptide on the MHC of the macrophage.
  3. Activation of the T helper cell and production of interleukins
  4. Interleukins initiate cell division into memory T cells, T helper 1 cell (TH1) and T helper 2 cell (TH2).
  5. T helper 1 cell recognizes peptide on the MHC of an infected macrophage and activate the infected macrophage to destroy the bacterial infections.
  6. T helper 2 cell attaches to the B cell to produce a humoral response.
84
Q

Mechanism of cell-mediated immunity in virally infected cells

A

The fragmented viral proteins bind to the class I MHC proteins.
They are transported to the surface of the cell so that the T cell can recognize them.
If they are recognized, the T cell can secrete perforins to destroy and lyse the infected cells.

85
Q

Large cluster of genes associated with Chromosome 6
Give rise to MHC protein molecules class I, II, III
Set genes that code for human cell receptors
Responsible for T-cell antigen recognition

A

Human Leukocyte Antigen (HLA) Complex

86
Q

Play a vital role in recognition of self and rejection of foreign tissue

A

HLA complex

87
Q

True or False.

MHC proteins have broad specificity to peptide antigens.

88
Q

True or False.
MHC polymorphism allow for binding of many specific and different peptides. Different alleles can bind and present different peptide antigens.

89
Q

Membrane proteins on APCs that display peptide antigens for recognition by T lymphocytes

A

Major Histocompatibility Complex (MHC)

90
Q

Act as “signpost” that alert immune system if foreign material is inside the cell

91
Q

Presentation of peptide on cell surface allows for pathogen surveillance and development of immune response

92
Q

True or False.

In polygenic and polymorphic MHCs, MHC genes codominantly expressed.

93
Q

Classes of MHC

A

Class I MHC genes
Class II MHC genes
Class III MHC genes

94
Q

Genes that encode Class 1 MHC genes

A

HLA-A, B and C

95
Q

Characteristics of Class I MHC genes

A

Made up of transmembrane glycoprotein and β2-microglobulin

Expressed on nearly all nucleated cells

96
Q

Function of Class I MHC gene

A

Code for markers that display unique characteristics of self

97
Q

Each human inherits a particular combination of Class I MHC (HLA)

A

Acquire peptide from cytosolic proteins

Present peptides to cytotoxic T cells (CD8 T cells)

98
Q 
True or False.
MHC class I locus contains genes that encode proteins required in antigen processing.
99
Q

Genes that encode Class II MHC genes

A

HLA-D region

100
Q

APCs where Class II MHC genes are found

A

Macrophages
B cells
Dendritic cells

*restricted distribution

101
Q

Function of Class II MHC genes

A

Involved in presenting antigens to T cells during cooperative immune reaction

102
Q

Mechanism of Class II MHC genes

A
  1. APCs take up pathogens & process within phagosomes
  2. Acquire peptides from intracellular vesicles
  3. Class II MHC on APCs present these fragments to helper T cells (CD4 T cells) to stimulate immune reaction
103
Q

Requires IFN-Y to be expressed in other cells.

A

Class II MHC genes

104
Q

This locus controls immune responsiveness and different allelic forms of these genes confer differences in the ability of an individual to mount an immune response

A

Class II MHC genes

105
Q

Encode proteins involved with the complement system

A

Class III MHC genes

106
Q

Mechanism of MHC

A

Macrophage → engulfment of microbe → fragmentation → → short peptides bound to MHC → goes to surface of the APC → → present antigen to helper t cell → binding these two would cause the macrophage to release IL-1 which acts on helper t cells → helper t cells release IL-2 which acts on itself and produces clones of helper t cells → participate in cell-mediated and humoral immunity → have the ability to attack the infected cells and secrete antibodies by the B cells

107
Q

True or False.

T cell cannot recognize the antigen if it is not bound to the MHC. T cells needs the MHC to present the antigen.

108
Q

Mechanism of MHC in viruses

A

Viral infected cell → binds with MHC proteins → brought to surface → binds with the T cells (for some time) → until it lyses the viral infected cell

109
Q

Occurs when T cells recognize Ag which is processed by APCs (antigen presenting cells) - macrophages & dendritic cells

A

Antigen recognition

110
Q

Hallmark of adaptive immune response

A

Antigen processing and presentation

111
Q

Major functions of Receptors

A
  1. To perceive and attach to antigens
  2. To promote recognition of self molecules
  3. To receive and transmit chemical messages among other cells of the system
  4. To aid in cellular development
112
Q

Some bacterial and viral antigens cause T cell activation through a special pathway, they are called

A

Superantigens

113
Q

Mechanism of superantigens

A

Do not require processing and can bind readily to MHC outside the binding cleft. As a result they can elicit release of large amounts of cytokines particularly IFN-Y which in turn activates macrophages to express IL-1,IL-6 and TNF-a causing “cytokine storm” and leading to shock and organ failure.

114
Q

Mechanism of Antigen recognition

A

Antigen ➡️ bound by APC ➡️ denatured/partial proteolysis within the endocytic vesicles of APC ➡️ fragments of antigen fuse with exocytic vesicles of APC containing MHC II ➡️ MHC II bound antigen is transported in the cell membrane for presentation

Microbiology and Parasitology (8 decks)

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