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Flashcards in B cells and Antibodies Deck (100)
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1
Q

T/F: there roughly 100 million kinds of B cells in the blood?

A

True; only about 30 of any one kind though.

2
Q

These are Y shaped proteins that attach to antigens and help identify harmful non-self things for destruction

A

Antibodies

3
Q

something that causes the immune system to create antibodies specifically targeting that something.

A

Antigen

4
Q

Antigen that a given B cell’s receptors recognize

A

Cognate Antigen

5
Q

part of the antigen that the antibody recognizes and attaches

A

Epitope

6
Q

part of the antibody that recognizes and attaches to the epitope

A

Paratope

7
Q

Where are antibodies made?

A

In B cells

8
Q

T/F: Antibodies have to be transcribed and translated by B cells like any other protein.

A

True

9
Q

T/F: B cell DNA has much less variety than other cells?

A

False; B cell DNA has much, much more variety.

10
Q

In genetic coding, three successive base pairs would be called what?

A

codon

11
Q

In genetic coding, each three consecutive bases represent what?

A

one amino acid

12
Q

In modular design, multiple copies of four gene segments code the antibody’s what?

A

heavy chain.

13
Q

What is the Fc Region?

A

a string of gene segments

14
Q

T/F: the light chain has many more gene segments to choose from.

A

True

15
Q

T/F: Junctional Diversity limits the B cell’s ability to make different antibodies.

A

False; in additon to modular design, junctional diversity helps bring the B cell’s ability to make up to about 100 million different antibodies.

16
Q

What are attached to the surface of B cells?

A

antibodies

17
Q

What are the antibodies on the surface of B cells called?

A

B cell receptors (BCRs)

18
Q

T/F: All B cells eventually find their specific match.

A

False; most B cells never find their cognate antigen.

19
Q

What are B cells that have never encountered their cognate antigen called?

A

naive or virgin B cells

20
Q

B cells that have been activated (found their cognate antigen) are called what?

A

Experienced B cells

21
Q

How many signals do B cells need to be activated?

A

Two

22
Q

What are the signals needed for B cells to be activated?

A

Clustering of B cell receptors and Co-stimulatory signal

23
Q

What are the two parts of the Co-stimulatory signal which helps to activate B cells?

A

T cell dependent and T cell independent (pattern recognition)

24
Q

Where are complement receptors and where are they located?

A

Proteins on the membrane of B cells

25
Q

What is the function of a B cell’s complement receptors?

A

they bind to the the complement protein fragments which are bound to the antigen.

26
Q

T/F: B cell’s BCRs can bind to the antigen.

A

True

27
Q

T/F: When BCR and complement receptors are brought together on an opsonized antigen, there is a massive increase in the number of BCRs that need to be clustered to signal to the nucleus.

A

False; this number decreases 100-fold

28
Q

What is it called when the B cell is stimulated by the antigen and a helper T cell?

A

T cell dependent co-stimulation

29
Q

Why do some antigens heavily cluster the BCRs?

A

they have repeating patterns of disaccharides

30
Q

When some antigens have repeating patterns and heavily cluster the BCRs, what is this considered?

A

T cell independent co-stimulation

31
Q

What is it referred to as when the B cell and the T cell meet their respective cognate antigens?

A

Dual confirmation of T cell dependent co-stimulation

32
Q

What is endocytosed when the B cell meets its cognate antigen?

A

Some of the cognate antigen

33
Q

What happens to the peptide fragments of the cognate antigen during T cell dependent co-stimulation?

A

they are presented on MHC II’s on the surface of the B cell

34
Q

What is the T cell’s cognate antigen during T cell Dependent Co-stimulation?

A

MHC II peptide on the B cell

35
Q

What does the T cell secrete that co-stimulates B cell?

A

cytokines

36
Q

What is it called when an antigen (mitogen) binds to B cell molecules that are not BCRs resulting in a polyclonal activation of B cells?

A

Un-natural T cell Co-stimulation

37
Q

What type of pathogen, with highly repetitive structures, can sometimes bind to B cell molecules that are not BCRs?

A

parasites

38
Q

When a polyclonal activation of B cells occurs, what type of cells are replicated?

A

B cells

39
Q

Do more B cells become plasma cells or memory B cells?

A

plasma cells

40
Q

T/F: Memory B cells are known as antibody factories.

A

False; plasma cells are antibody factories

41
Q

T/F: one plasma cell can produce 200 antibodies per second.

A

False; 2000 antibodies/sec

42
Q

What happens to B cells after activation and proliferation?

A

maturation process

43
Q

What are the three parts of B cell maturation?

A

Somatic Hypermutation, Career Decision, and Class switching.

44
Q

How does Somatic Hypermutation affect the affinity of the BCR for its cognate antigen?

A

It increase the affinity.

45
Q

What are the “career choices” for a B cell?

A

Plasma cell or Memory cell

46
Q

What does a B cell change during the Class Switching period of Maturation?

A

the class of antibody it produces

47
Q

When does somatic Hypermutation occur in relation to the V, D, and J gene segments?

A

It occurs AFTER the gene segments have been selected

48
Q

What part of the antibody is changed during Somatic Hypermutation?

A

the antigen binding region

49
Q

B cells with BCRs having higher affinity for their cognate antigen is a result of what?

A

Somatic Hypermutation

50
Q

How long do Plasma cells live?

A

only for a few days

51
Q

How long do Memory B cells last?

A

greater than 50 years

52
Q

What are the five classes antibodies fall into?

A

IgG, IgA, IgM, IgE, and IgD (GAMED)

53
Q

What determines the class of antibody?

A

the constant (Fc) region of its heavy chain

54
Q

What occurs when the B cells “cut and paste” different constant regions?

A

Class switching

55
Q

What class of antibody is produced (mainly) when a naive B cell is first activated?

A

IgM

56
Q

Which class of antibody is not considered one of the four main classes?

A

IgD

57
Q

What are the two main functions of antibodies?

A

Opsonization and Neutralization of exotoxins

58
Q

Which class of antibody is passed from the mother’s blood to the fetus via the placenta?

A

IgG

59
Q

Which class of antibody is the longest lived?

A

IgG (3 weeks)

60
Q

Serum (blood) contains more of what class of antibody than any other?

A

IgG

61
Q

Which class of antibody guards the mucosal surfaces?

A

IgA

62
Q

Which class of antibody coats pathogens and blocks attachment?

A

IgA

63
Q

Which class of antibody is the most abundant in the body?

A

IgA

64
Q

How much of normal fecal matter is rejected bacteria?

A

about 30%

65
Q

Which class of antibody is like two IgGs clipped together (two antigen binding areas)

A

IgA

66
Q

What is the first immunoglobulin to be made following antigen recognition?

A

IgM

67
Q

Which class of antibody is equal in size to five IgGs?

A

IgM

68
Q

Which class of anitbody has a half-life of about one day?

A

IgM

69
Q

Which class of antibody is known for immoblizing the antigen?

A

IgM

70
Q

Which class of antibody activates the Complement System (classical pathway)

A

IgM

71
Q

Which class of antibody is made in response to allergen exposure?

A

IgE

72
Q

Which class of antibody binds to the surface of mast cells?

A

IgE

73
Q

What causes shock during allergen exposure?

A

degranulatiing mast cells

74
Q

What are allergens?

A

antigens that can cause an allergic reaction

75
Q

What type of WBCs protect against parasites?

A

Mast Cells

76
Q

T/F: Mast cells can live for years

A

True

77
Q

What cells phagocytize and opsonize bacteria?

A

Mast cells

78
Q

What do mast cells store?

A

harsh chemistry (histamine)

79
Q

Which class of antibody do mast cells bind to when fighting parasites?

A

IgE

80
Q

T/F: Massive degranulation throughout the body can increase blood volume drastically to the point of a heart attack.

A

False; it can decrease it enough to cause a heart attack

81
Q

How can histamine cause suffocation?

A

contracts the smooth muscle of the respiratory tract

82
Q

What is anaphylaxis?

A

an acute allergic reaction

83
Q

What is the opposite of anaphylaxis?

A

Prophylaxis

84
Q

to provide protection; prevent disease; guard or prevent before hand

A

prophylaxis

85
Q

Which class of antibody was discovered in 1964?

A

IgD

86
Q

Which class of anitbody has an unclear function?

A

IgD

87
Q

Which class of antibody is a lot like IgM in that B cells don’t make it until they leave the bone?

A

IgD

88
Q

Which class of antibody is a great complement fixer and good opsonizer?

A

IgM

89
Q

Which class of antibody causes anaphylactic shock?

A

IgE

90
Q

Which class of antibody is secreted in milk?

A

IgA

91
Q

What is class switching controlled by?

A

cytokines (T cells)

92
Q

T/F: different pathogens provoke different cytokines

A

True

93
Q

T/F: cells from different areas of the body make characteristic mixes of cytokines.

A

True

94
Q

T/F: B cells are lymphocytes.

A

True

95
Q

T/F: B cells have very diverse, non-specific receptors (BCRS)

A

False; B cells have very diverse, SPECIFIC receptors (BCRs)

96
Q

What do BCRs bind to?

A

antigens (carbs or proteins)

97
Q

Cross linking of BCRs and sometimes the presence of helper T cells is indicative of what type of activation?

A

Activation of naive B cells

98
Q

What do activated B cells (plasma cells) make?

A

Antibodies

99
Q

What stage of maturation helps B cells get an even better fit to the antigen?

A

Somatic Hypermutation

100
Q

What careers are available to mature B cells?

A

memory cell or antibody factory (plasma cell)