Deck 24: A: Immune System

Question 1

To function independently in the immune process,both B cells and T cells must become thymocytes during development.

Answer 1

False

Question 2

The inflammatory response is the body's first line of defense.

Answer 2

False

Question 3

All antigens have epitopes of the same shape.

Answer 3

False

Question 4

Phagocytosis is a nonspecific defense mechanism.

Question 5

The heavy chains in an immunoglobulin molecule are about twice as long and weigh about twice as much as light chains.

Question 6

The combining site on an antibody determines the specificity of that antibody for an antigen.

Question 7

Natural killer cells are a group of neutrophils that kill many types of tumor cells and cells infected by different kinds of viruses.

Question 8

Antigens are macromolecules that induce the immune system to take certain actions.

Question 9

The cloning of T cells produces both memory cells and plasma cells.

Question 10

Complement is a chemical produced by cells after they become infected by a virus.

Question 11

Cytokines include leukotrienes,interferons,and histamine.

Question 12

The second stage of B cell development usually takes place in the lymph nodes and spleen.

Question 13

Diapedesis is the process by which neutrophils migrate out of the bloodstream and around the tissue cells to the injury site.

Question 14

Another name for antigenic determinants is epitopes.

Question 15

Many of the inflammation mediators act as chemotactic factors.

Question 16

Neutrophils function in the immune system by producing immunoglobulins.

Question 17

Interferon mainly interferes with the ability of bacteria to produce disease.

Question 18

Most antigens are large protein molecules foreign to the body.

Question 19

T cell immune mechanisms are classified as antibody-mediated immunity.

Question 20

Inactive B cells produce antibodies that insert on their plasma membranes to serve as antigen receptors.

Question 21

When antibodies cause antigens to agglutinate,it allows them to be disposed of by phagocytes more easily.

Question 22

Inherited immunity and acquired immunity are forms of specific immunity.

Question 23

Suppressor T cells help B cells differentiate into antibody-secreting plasma cells by secreting cytokines such as interleukin-2 and interleukin-4.

Question 24

Suppressor T cells function by inhibiting T cell formation.

Question 25

Haptens are sometimes called incomplete antigens.

Question 26

An antigen consists of two heavy and two light polypeptide chains.

Question 27

Unlike B cells,T cells do not display antigen receptors on their surface membranes.

Question 28

The somatic recombination hypothesis is one possible explanation for the diversity of antibodies.

Question 29

The fetal liver may act as the site for the first stage of T cell development.

Question 30

Phagocytosis is the "first line of defense" in nonspecific immunity.

Question 31

Passive immunity generally lasts longer than active immunity.

Question 32

All of the cells in a clone of plasma cells produce identical antibodies.

Question 33

Each light chain in an antibody molecule contains a constant region that consists of 446 amino acids.

Question 34

An antibody has one antigen-binding site.

Question 35

The most numerous type of phagocyte is the macrophage.

Question 36

Contact points between immune cells are sometimes called immunological synapses.

Question 37

Humoral immunity occurs within the plasma.

Question 38

The surface membranes of cancer cells are thought to have abnormal antigens.

Question 39

T cells,by definition,are lymphocytes that have passed through the thyroid gland.

Question 40

Natural killer cells are 15% of the total lymphocyte cell number.

Question 41

The specific immune system has a more rapid response than the nonspecific immune system.

Question 42

T cells secrete antibodies.

Question 43

A chemotactic factor attracts antibodies to the site of infection.

Question 44

A macrophage can migrate out of the bloodstream.

Question 45

Cell-mediated immunity involves T cells.

Question 46

The immune mechanism that provides a defense by acting against cancer is termed nonspecific immunity.

Question 47

One reason for species resistance is the difference in molecules on the cell membrane of different species.

Question 48

An antibody consists of two heavy and one light polypeptide chains.

Question 49

Tobacco mosaic virus can destroy tobacco plants.It has no effect on humans.This is an example of species resistance.

Question 50

Macrophages are a group of lymphocytes that kill many types of tumor cells and cells infected by different kinds of viruses.

Question 51

CD4 and CD8 T cell subsets are clinically important in diagnosing AIDS.

Question 52

Plasma cells can secrete as many as 2000 antibodies per minute.

Question 53

IgD is the most understood antibody.

Question 54

The characteristic signs of inflammation are the results of increased blood flow and increased vascular permeability.

Question 55

In phagocytosis,a foot-like projection,called a phagosome,extends toward a microorganism.

Question 56

Most of the pus surrounding an inflammation site consists of dead or damaged tissue cells.

Question 57

The chemical messengers that T cells release into inflamed tissues are called lymphotoxins.

Question 58

IgM is the most predominant class of immunoglobulins in the body.

Question 59

Digestive enzymes and hydrogen peroxide are added to a phagosome to digest the phagocytized microorganism.

Question 60

The first vaccination provided immunity against the chickenpox virus.

Question 61

When pseudopods form a phagocyte,completely surrounding an organism and forming a sac around it,the structure formed is called a phagosome.

Question 62

Natural killer cells are lymphocytes that are actually part of nonspecific immunity.

Question 63

Because of the random nature of antibody protein synthesis,it is possible to have an "anti-self" B cell.

Question 64

Antigens activate B cells.

Question 65

Species resistance refers to a phenomenon in which the genetic characteristics common to a species provide defense against certain pathogens.

Question 66

In humans,bursa equivalent tissue is the site for B-cell development.

Question 67

Plasma cells must be in a constant state of protein synthesis to accomplish their function.

Question 68

The ability of our immune system to attack abnormal or foreign cells but spare our own normal cells is called innate immunity.

Question 69

Passive immunity provides more rapid protection than does active immunity.

Question 70

A person's natural killer cells usually kill cells of their own body.

Question 71

In an antibody,the light chain makes up the variable region and the heavy chain makes up the constant region.

Question 72

Interleukins are cytokinins.

Question 73

The role of fibroblasts in the inflammation response is to lay down a collagen web to try to isolate the infecting organism.

Question 74

One function of phagocytes is to function as antigen-presenting cells.

Question 75

Even though tumor cells are part of your body,your immune system treats them as "foreign" and tries to destroy them.

Question 76

Both B and T lymphocytes develop from hematopoietic stem cells.

Question 77

Once released from the bone marrow,the B cells migrate to the bursa of Fabricius to complete their development.

Question 78

Cytokines are chemicals released from cells to trigger or regulate both innate and adaptive immune responses.

Question 79

There are almost 100 billion lymphocytes in the body's immune system.

Question 80

Complement can be activated only by the specific immune system.