Deck 16: Adaptive Immunity

Question 1

Lymph node aggregates are found in all of the following areas EXCEPT:

A) the abdomen.
B) the axilla (armpit).
C) the neck.
D) the groin.
E) the wrist.

Answer 1

E

Question 2

Antigens are

A) proteins the body produces against invading substances.
B) cells that protect the body against invaders.
C) specific molecules that the body recognizes as foreign.
D) enzymes secreted to destroy a pathogen's wall.
E) proteins on the surface of our cells that pathogens attach to.

Answer 2

C

Question 3

Under normal situations, lymphocytes do not act against autoantigens because

A) antibodies produced against autoantigens are destroyed.
B) they never have binding sites that are complementary to autoantigens.
C) antibodies prevent them from binding to the body's own cells.
D) they identify cells with autoantigens as belonging to the body and do not attack them.
E) lymphocytes that bind to autoantigenes undergo apoptosis.

Answer 3

E

Question 4

Which of the following cytokines acts as a signal between leukocytes?

A) interleukins
B) tumor necrosis factors
C) chemokines
D) interferons
E) growth factors

Question 5

The most prevalent type of antibody in the blood is

A) IgG.
B) IgE.
C) IgD.
D) IgM.
E) IgA.

Question 6

Secretory component is associated with which of the following?

A) IgD
B) IgG
C) IgA
D) IgM
E) IgE

Question 7

Which of the following characteristics would NOT make a molecule more antigenic?

A) a molecule with many epitopes
B) a molecular mass less than 5000 daltons
C) a stable molecule that maintains a definite shape
D) a complex molecule with many antigenic determinants
E) complex molecules like a glycoprotein or phospholipid

Question 8

Both IgM and IgA have which of the following functions?

A) agglutination of antigens
B) neutralization of antigens
C) complement activation
D) Both A and B are correct.
E) A, B, and C are correct.

Question 9

Which of these statements concerning B cell receptors (BCRs) is incorrect?

A) Scientists estimate that each person forms at at least 109 different types of B lymphocytes with a set of distinct BCRs.
B) Each B lymphocyte is randomly generated with antibody- variable regions that determine its BCR.
C) They are complementary in shape to the antigenic determinants of antigens that they may or may not encounter.
D) They are formed in response to an encounter with an antigen.
E) They are bound to the surface of B lymphocytes and have two antigen- binding sites.

Question 10

The type of immunoglobulin produced during the initial stages of an immune response is

A) IgD.
B) IgM.
C) IgE.
D) IgA.
E) IgG.

Question 11

Which of the following statements about lymphocytes is incorrect?

A) Lymphocytes have integral surface glycoproteins by which they can be recognized.
B) Once they are mature, they migrate to the bone marrow.
C) The glycoproteins on the surface of a lymphocyte are designated with the prefix CD, for cluster of differentiation.
D) B and T lymphocytes cannot be differentiated under the microscope.
E) There are 250 types of CD molecules, some of which are present on lymphocytes.

Question 12

Which of the following statements concerning the chemical structure of an antibody is incorrect?

A) Antibodies have two short peptide chains known as light chains.
B) Antibodies are formed of four polypeptide chains.
C) There are five types of Fc regions.
D) Antibodies have two long peptide chains known as heavy chains.
E) The stem and arms are connected by hydrogen bonds.

Question 13

The designation "B" for B lymphocytes comes from

A) the bursa of Fabricius in birds where these cells were first identified.
B) the sequence in which these lymphocytes were discovered.
C) the bone marrow where these cells are produced.
D) the fact that these cells produce antibodies.
E) the ability of these cells to provide immunity through body fluids.

Question 14

The Fc portion of an antibody is formed by

A) the lower portions of the heavy chains.
B) one light chain and one heavy chain.
C) the upper portions of the light chains.
D) the upper portions of the heavy chains.
E) the lower portions of the light chains.

Question 15

All of the following are true of lymph EXCEPT:

A) It flows toward the heart.
B) It has no unique pump.
C) Lymphocytes and antibodies flow through the lymph.
D) It comes from fluid that has leaked out of blood vessels.
E) It contains wastes such as degraded proteins and toxins.

Question 16

An invading bacterial cell would be a source of which of the following?

A) endogenous antigens
B) self- antigens
C) exogenous antigens
D) antibody antigens
E) autoantigens

Question 17

Which of the following statements about T lymphocytes is incorrect?

A) T lymphocytes are called such because they mature in the thymus.
B) There are three types of T lymphocytes.
C) T lymphocytes act directly against antigens and produce the cell- mediated immune response.
D) There are fewer types of T cell receptors than B cell receptors and therefore the T lymphocyte cannot react with as many types of antigens.
E) T lymphocytes have TCRs that recognize antigen only if it is bound to MHC.

Question 18

Which of the following is NOT considered a function of an antibody?

A) They can bind two microbial cells together, leading to agglutination.
B) They can enhance phagocytosis.
C) They can produce toxins that directly kill bacteria.
D) They can block the attachment molecules on the surface of bacteria and viruses in order to prevent them from attaching to their target cells.
E) They can bind to crucial parts of toxins and deactivate them.

Question 19

The humoral immune response is attributed to the action of

A) monocytes.
B) neutrophils.
C) B lymphocytes.
D) T lymphocytes.
E) macrophages.

Question 20

Peyer's patches are found in the

A) mammary glands.
B) spleen.
C) tonsils.
D) small intestine.
E) respiratory tract.

Question 21

Which of the following statements concerning T- independent responses is incorrect?

A) They are slow responses.
B) Cytokines are required for their success.
C) T- independent antigens produce extensive cross- linking between BCRs.
D) They can involve Toll- like receptors on B cells.
E) They are weak and disappear quickly.

Question 22

Which of the following statements concerning adaptive immunity is incorrect?

A) It is the third line of defense.
B) It takes a long time to respond whenever it encounters a pathogen.
C) It is acquired.
D) It is the body's ability to respond to specific invading pathogens.
E) It has memory.

Question 23

Class II MHC (major histocompatibility) antigens are only found on

A) muscle.
B) red blood cells.
C) lymphocytes and antigen- presenting cells.
D) nucleated cell membranes.
E) the skin.

Question 24

Which of the following statements about helper T cells is incorrect?

A) They can be distinguished from other T lymphocytes by the presence of certain glycoproteins.
B) They function in conjunction with B cells.
C) They secrete messenger proteins called perforins.
D) There are two types: TH1 and TH2.
E) They are destroyed in HIV- infected individuals.

Question 25

Cell- mediated immune responses are directed against all of the following EXCEPT:

A) viruses.
B) tumor cells.
C) extracellular bacteria.
D) intracellular protozoa.
E) Mycobacterium tuberculosis.

Question 26

The immunological synapse refers to the

A) binding of a monocyte or macrophage to the antigen so that it can act as an antigen- presenting cell.
B) interaction of the many cytokines produced by different immunological cells.
C) interaction between a T cell and an antigen- presenting cell to produce a specialized contact area for communication between these cells.
D) interaction between lymphocytes and foreign antigens to produce memory cells.
E) activation of a B cell to become a plasma cell.

Question 27

Molecules with a molecular mass less than 5000 daltons can become antigens when they bind to carrier molecules.

Question 28

Large molecules such as polymers with repeating subunits make good antigens.

Question 29

The MALT lacks the tough outer capsule of a lymph node, but functions in the same way.

Question 30

The perforin- granzyme pathway involves

A) binding CD95L to infected cells, which eventually leads to cell apoptosis.
B) presenting the foreign antigen to B cells.
C) the production of antibodies toward the invading pathogen.
D) the production of fever, which kills the pathogen.
E) the synthesis of special cell- killing proteins that act on infected or abnormal cells.

Question 31

Which of the following is NOT considered part of the immune system?

A) the lymph nodes
B) the liver
C) the spleen
D) Peyer's patches
E) the tonsils

Question 32

A single B lymphocyte can recognize multiple antigenic determinants.

Question 33

What type of immunity is produced by the body when a person receives a vaccine?

A) artificially acquired passive immunity
B) naturally acquired passive immunity
C) artificially acquired active immunity
D) inborn immunity
E) naturally acquired active immunity

Question 34

Which of the following recognizes and binds to MHC II antigens and helps stabilize the binding of antigenic determinants to T cell receptors?

A) CCR3
B) CD26
C) MHC I
D) CD4
E) CCR5

Question 35

Major histocompatibility antigens are

A) glycoproteins found on the surface of most vertebrate animals.
B) antigens that provoke allergic reactions.
C) antigens attached to foreign invaders.
D) not really antigens, but rather antibodies produced to mask foreign antigens.
E) antigens that must be processed by cells called histiocytes in order to be recognized by the immune system.

Question 36

Antibodies from animals such as horses constitute artificially acquired passive immunity.

Question 37

Enhanced immune responses to subsequent exposures to an antigen to which the body has already been exposed are known as

A) autoimmune responses.
B) primary immune responses.
C) allergic responses.
D) third- degree immune responses.
E) memory responses.

Question 38

All of the following statements are true of the humoral immune response EXCEPT:

A) Most antigens activate B cells without the help of T cells.
B) IgM are the first immunoglobulins to be produced.
C) Active B cells differentiate into memory B cells and plasma cells.
D) Plasma cells produce antibodies.
E) It is a third line of defense against exogenous antigens.

Question 39

The major histocompatibility antigens are coded for by genes on which chromosome number?

A) 21
B) 6
C) 3
D) 12
E) 16

Question 40

Which of the following statements concerning plasma cells is incorrect?

A) They live a long time and function as memory cells.
B) They secrete antibody molecules with antigen- determining sites that only act against specific antigen determinants.
C) They produce 2000 antibodies per second.
D) They are activated B cells.
E) The antibodies they produce can remain in circulation for weeks.

Question 41

The ability of the body to recognize its own antigens is called .

Question 42

The body recognizes antigens by the three- dimensional shapes of regions known as .

Question 43

Humoral immunity is mediated by membrane- bound proteins and cytokines.

Question 44

The surface of each B lymphocyte is covered with about 500,000 identical copies of .

Question 45

Historically, body fluids such as lymph and blood were known as .

Question 46

B lymphocytes can bind directly to large antigens with repeating polysaccharide subunits, such as a bacterial
capsule that has antigenic determinants known as .

Question 47

A humoral immune response occurs when an APC binds to a

Question 48

Clonal deletion removes lymphocytes that react to .

Question 49

IgM is the most common class of antibodies in the blood.

Question 50

The variable regions from the light and heavy chains of an antibody combine to form .

Question 51

Cytokines are soluble regulatory proteins that act as intercellular signals and include substances such as interleukins, interferon, and growth factors.

Question 52

Antigen- presenting cells (APCs) include monocytes, macrophages, and their closely related relatives, such as
.

Question 53

Under normal conditions, _ takes place when a lymphocyte binds to an autoantigen.

Question 54

Experiments in which tissue was transferred from one animal to another led to tdhiescovery of _ antigen

Question 55

When a T cell's CD95L binds to the CD95 on a target cell, apoptosis is triggered.

Question 56

Because T cells act directly against antigens, their activity is considered part of the immune response.

Question 57

Secretory IgA and the IgA in the blood have the same chemical composition.

Question 58

When a T cell and an antigen- presenting cell interact, a specialized contact called a(n) _ forms between them.

Question 59

An antigen produced by a pathogen while living inside a cell is known as a(n) antigen.

Question 60

is required for helper T cells to bind antigen.

Question 61

Discuss the basic structure of the antibody molecule.

Question 62

What are the steps involved in B cell activation?

Question 63

Describe the mechanisms of action of antibodies.

Question 64

What are the groups of antigens according to their relationship to the body?

Question 65

Describe the different types of acquired immunity.