The Adaptive Immune System

Question 1

The adaptive immune system provides __________ defense.

Answer 1

specific.

Question 2

What is specificity based on?

Answer 2

Antigen recognition.

Question 3

Most immunogenic antigens are _________.

Answer 3

proteins.

Question 4

When first encountering an antigen, how long will the adaptive immune system take to develop?

Answer 4

5-7 days.

Question 5

What are the 2 types of cells mediating the adaptive immune system?

Answer 5

B-lymphocytes & T-lymphocytes.

Question 6

B-lymphocytes provide _______ immunity while T-lymphocytes provide ____-________ immunity.

Answer 6

humoral; cell-mediated.

Question 7

B-lymphocytes produce _________.

Answer 7

cytokines.

Question 8

What are cytokines?

Answer 8

Chemical signals that can change the behaviour of other cells.

Question 9

Cytokines can cause B cell _____________ & _____-_________.

Answer 9

proliferation; class-switching.

Question 10

What happens when a B cell undergoes class-switching?

Answer 10

Changing the Ig produced without changing the antigen specificity.

Question 11

Are B cells antigen presenting cells (APCs)?

Answer 11

Yes.

Question 12

Where are B cells produced?

Answer 12

Bone marrow.

Question 13

Where do B cells mature?

Answer 13

Bone marrow.

Question 14

Is B cell production/maturation antigen dependent or independent?

Answer 14

Antigen independent.

Question 15

Where are B cells activated and differentiated? Is this process antigen dependent or independent?

Answer 15

Peripheral lymphoid organs (ex: lymph glands).

Antigen dependent.

Question 16

What is the difference between thymus-dependent (TS) and thymus-independent (TI) antigens?

Answer 16

TD = proteins, TI = other molecules.
TD requires helper T-cells.
TI: no memory cells amde.

Question 17

What is the Fab region on an antibody?

Answer 17

The variable antigen binding site.

Question 18

What is the Fc region on an antibody?

Answer 18

Constant region that is recognized by other immune cells that have an Fc receptor (binding site).

Question 19

What are the 5 functions of antibodies?

Answer 19

1. Opsonization.
2. Complement activation.
3. Agglutination.
4. Neutralization.
5. Antibody-dependent, cell-mediated cytotoxicity.

Question 20

What are the 5 classes of antibodies?

Answer 20

IgG.
IgM.
IgA.
IgE.
IgD.

Question 21

Which class of antibody is most common in the serum?

Answer 21

IgG.

Question 22

Which class of antibody is transferred from mother to fetus via the placents?

Answer 22

IgG.

Question 23

Which class of antibody is most efficient at activating the complement?

Answer 23

IgM.

Question 24

Which class of antibody is first synthesized by neonates?

Answer 24

IgM.

Question 25

Which class of antibody is the first to be synthesized in a primary response?

Answer 25

IgM.

Question 26

IgM is secreted by plasma cells as a _______.

Answer 26

pentamer.

Question 27

What are monomers of antibodies held together by?

Answer 27

J-chains (joining chain).

Question 28

Which class of antibody is predominant in external secretions?

Answer 28

IgA.

Question 29

Which class of antibody is secreted in the breast milk and transferred to babies in that way?

Answer 29

IgA.

Question 30

Which class of antibody is responsible for allergies?

Answer 30

IgE.

Question 31

Which class of antibodies is important for neutralizing parasites?

Answer 31

IgE.

Question 32

What is the main difference between serum and plasma?

Answer 32

Serum contains no active blood clotting proteins. | Plasma contains intact blood clotting proteins that have not been activated.

Question 33

Cytotoxic T lymphocytes are also known as:

Answer 33

CD8+.

Question 34

Helper T lymphocytes are also known as:

Answer 34

CD4+.

Question 35

Where are T cells produced?

Answer 35

Bone marrow.

Question 36

Where do immature T cells go to develop?

Answer 36

thymus.

Question 37

What 2 factors is the development of immature T cells dependent on?

Answer 37

self MHC I molecules & the antigen.

Question 38

Where are T cells activated?

Answer 38

Peripheral lymphoid organs.

Question 39

What 2 molecules are secreted by activated T cells to destroy target cells?

Answer 39

Perforin & granzyme.

Question 40

In activated T cell clonal expansion, most cells will remain as ______ cells while a small percentage will become ______ cells.

Answer 40

killer; memory.

Question 41

In what situations will Th1 and Th2 be useful?

Answer 41

Th1: against intracellular pathogens. Th2: against extracellular pathogens.

Question 42

In activated Th cell clonal expansion, most cells will remain in the system as ______ cells while a small percentage will become ______ ______ cells.

Answer 42

helper; memory helper.

Question 43

What is wrong with T cells in autoimmunity?

Answer 43

T cells are unable to differentiate self from non-self.

Question 44

What is wrong with T cells in partial immunodeficiency?

Answer 44

Loss of T cell function or numbers.

Question 45

What is the difference between apoptosis & necrosis?

Answer 45

Apoptosis is programmed cell death - relatively normal & does not trigger inflammation. Necrosis is caused by cell injury or infections/toxins (extrinsic factors) -- it is detrimental, abnormal & accompanied by an inflammatory response.