Deck 10: Defense Systems

Question 1

Self-recognition in mammals depends in part on ________.

A) the presence of interleukins
B) innate immunity.
C) the presence of cytokines
D) Toll-like receptors
E) all of these.

Answer 1

Toll-like receptors

Question 2

Which of the following are NOT correctly paired?

A) cytokines and nongland cells
B) vertebrate immune cell communication and immunosynapse
C) inflammation and second line of defense
D) amoebocytes and hemocytes
E) antimicrobial peptides and opsonin

Answer 2

antimicrobial peptides and opsonin

Question 3

Which of the following leukocytes are phagocytic?

A) natural killer cells
B) neutrophils
C) eosinophils
D) natural killer cells and neutrophils
E) neutrophils and eosinophils

Answer 3

neutrophils

Question 4

Mast cells are ________ .

A) are transformed monocytes
B) are a subset of B-cells
C) a subset of T-cells
D) are macrophages that remain in the circulation
E) are analogous to sensing-integrating endocrine glands.

Question 5

The ________ is/are the origin of all leukocytes.

A) lymph nodes
B) spleen
C) tonsils
D) bone marrow
E) thymus

Question 6

Which of the following statements about sweat glands is NOT true?

A) Sweat glands are derived from the epidermis.
B) Sweat glands are important in thermoregulation.
C) Sweat glands produce anti-microbial compounds.
D) Sweat glands produce sebum.
E) None of these.

Question 7

Which of the following skin cells does NOT play a role in immune function?

A) melanocytes
B) keratinocytes
C) dendritic cells
D) Granstein cells
E) All of these play a role in immune function.

Question 8

The secretion of histamine by mast cells causes

A) vasodilation, bringing phagocytic cells to the site of infection.
B) invading bacterial cells to lyse.
C) invading bacterial cells to coagulate.
D) all of these.
E) none of these.

Question 9

Neutrophils secrete ________ that kill invading microbes.

A) nitric oxide
B) cathelicidins
C) interleukin-1
D) TLRs

Question 10

As part of their defense against bacteria, neutrophils secrete the iron-binding protein ________, making iron unavailable for bacterial multiplication.

A) transferrin
B) heme
C) lactoferrin
D) lactose
E) macferrin

Question 11

The function of kallikrein is to

A) activate the complement system.
B) enhance vascular permeability.
C) convert kininogens to kinins.
D) activate pain receptors at the site of a wound.
E) act as chemotaxins.

Question 12

Interleukin-6

A) functions as an endogenous pyrogen.
B) stimulates the release of prostaglandins within the hypothalamus.
C) decreases plasma iron concentrations
D) two of these.
E) all of these.

Question 13

Released by cells as part of the nonspecific, second line of defense against infection, interferon functions in

A) interfering with the replication of extracellular bacteria.
B) inhibiting replication of viruses in cells infected with them.
C) preventing viruses from adhering to the cell surface and injecting their genetic material.
D) is a cytokine that blocks replication of virally infected cells.
E) more than one of these.

Question 14

________ nonspecifically cause virus-infected cells to lyse.

A) Cytotoxic T-cells
B) Natural killer cells
C) Lymphocytes
D) Macrophages
E) Granulocytes

Question 15

Lymphoid tissue

A) stores lymphocytes.
B) processes lymphocytes.
C) includes the adenoids.
D) is found in the lining of the digestive tract.
E) all of these.

Question 16

________ is a hormone responsible for maintaining T-cell lineages.

A) Interferon
B) Cathelicidin
C) Thymosin
D) Erythropoietin
E) Insulin

Question 17

Which of the following statements is NOT true?

A) The more complex a foreign molecule the greater its antigenicity.
B) Isolated molecules may act as antigens.
C) Large polysaccharides may act as antigens.
D) T cells reside in colonies.
E) The key to B- and T-cell specificity is the TLRs present in their membrane that
Binds antigens.

Question 18

The specificity of an antibody for its antigen is determined by the

A) structure of the arm region of the "Y."
B) structure of the tail region of the "Y."
C) Fc region of the antibody.
D) variability between the arm and tail region of the "Y".
E) process of optimization during development.

Question 19

Neutralization by antibodies refers to a process through which

A) antibodies buffer the pH of plasma in a way that is inhospitable to invading bacteria.
B) antibodies crosslink antigens into chains or clumps, preventing them from exerting their pathogenic effects.
C) antibodies combine with bacterial toxins, preventing them from harming susceptible cells.
D) none of these.

Question 20

Memory cells are

A) hippocampal neurons.
B) exocrine cells that produce milk.
C) dormant, non-secreting B-cells.
D) dormant, non-secreting T-cells.
E) antibody secreting B-cells.

Question 21

The phenomenal diversity of antibodies produced by an individual is possible because

A) B-cells contain more genes than other cells of the body.
B) once the gene encoding an antibody is transcribed, the mRNA is sloppily translated, in effect introducing mutations (and therefore diversity) post-translationally.
C) even though they have the same number of genes as other cells of the body, virtually all of their genome is dedicated to antibody genes.
D) the gene fragments encoding antibodies are cut, reshuffled and spliced during a B-cell's development, enabling innumerable amino acid sequences to be generated.
E) None of these.

Question 22

Although B-cells (as plasma cells) are specialized to secrete antibodies, they require the assistance of a number of other types of cells, including

A) macrophages.
B) dendritic cells.
C) T-helper cells.
D) all of these.
E) none of these.

Question 23

The rate of signal transfer between helper T cells and antigen presenting cells is increased by the presence of

A) cytokines.
B) interleukins.
C) MHC I.
D) MHC II.
E) nanotubes.

Question 24

Immune tolerance preventing a normal immune system from attacking the individual's own tissues involves

A) clonal deletion.
B) clonal anergy.
C) receptor editing.
D) immunological ignorance.
E) all of these.

Question 25

Immune privilege refers to

A) the existence of an immune system in a limited number of taxa.
B) the inhibition throughout life of immune cells that are specific for the body's own tissues.
C) the ability of the eyes to escape immune attack.
D) two of these.

Question 26

The major histocompatibility complex

A) was first observed in virally infected fish.
B) is a group of cells responsible for presenting antigens to B-cells to stimulate antibody production.
C) is a cluster of genes which encode self-antigens.
D) is the membrane glycoprotein and associated antigen presented to B-cells.
E) none of these.

Question 27

Immune defense against cancer depends on

A) the release of inteferon.
B) the presence of macrophages.
C) the presence of cytotoxic cells.
D) two of these.
E) all of these.

Question 28

Although many cells undergo mutation during an animal's lifetime, malignancy is rare since

A) only a small fraction of the genome encodes proteins involved in cell cycle regulation, so the probability of mutation of these genes is low.
B) generally multiple mutations are required to turn a normal cell into a cancer cell.
C) immune surveillance results in nascent cancer cells being eliminated by cytotoxic T-cells.
D) all of these.
E) none of these.

Question 29

IL-1 release by immune cells results in the secretion of glucocorticoids such as cortisol. Cortisol, in turn,

A) mobilizes amino acids.
B) mobilizes energy reserves and enhances immune function by making more energy available.
C) suppresses immune function.
D) mobilize energy reserves and suppress immune function.
E) does all of these.

Question 30

As a part of their specific immune defenses Drosophila rely on

A) Down syndrome cell-adhesion molecule receptors.
B) amoebocytes.
C) Toll receptors.
D) drosomycins.
E) two of these.

Question 31

Until recently, acquired immunity was thought to only occur in jawed vertebrates. Which of the following observations suggest that this is NOT the case?

A) Phenoloxidase activity enables hemocytes to form an impermeable wall of melanin around an infecting pathogen.
B) Invertebrate immune cells secrete an IL-1 like compound.
C) Invertebrates produce lectins, which coat bacterial cells, priming them for phagocytosis.
D) Copepods become resistant to tapeworms after an initial exposure.
E) None of these.

Question 32

The shark immune system has been so effective that they have survived longer than
mammals have been on earth.

Question 33

Carotenoids suppress inflammatory reactions in birds.

Question 34

Invertebrates such as sea stars secrete a cytokine similar to interleukin-2 found in
vertebrates.

Question 35

Most vertebrate have two lines of defense.

Question 36

In addition to producing melanin, melanocytes play a role in immunity.

Question 37

SALT refers to the epidermal components of the immune system.

Question 38

Mast cells release histamine that will act as an autocrine cytokine and stimulate further
release of histamine.

Question 39

Many of the vertebrate complement proteins are related to the defensins found in
invertebrates.

Question 40

The Toll-like receptors of the innate system bind numerous generic markers on
microorganisms.

Question 41

T cell growth factor, IL-2, secreted by helper T cells is one of several interleukins that
stimulate B cells.

Question 42

Match each sentence with the most appropriate choice:

-Innate immune system

A) nonspecific response
B) specific response
C) T-cell
D) B-cell
E) IgE
F) Helper T-cells
G) T-cell growth factor
H) HIV
I) virtually all nucleated body cells
J) special types of immune cells

Question 43

Match each sentence with the most appropriate choice:

-Acquired immune system

A) nonspecific response
B) specific response
C) T-cell
D) B-cell
E) IgE
F) Helper T-cells
G) T-cell growth factor
H) HIV
I) virtually all nucleated body cells
J) special types of immune cells

Question 44

Match each sentence with the most appropriate choice:

-Thymus

A) nonspecific response
B) specific response
C) T-cell
D) B-cell
E) IgE
F) Helper T-cells
G) T-cell growth factor
H) HIV
I) virtually all nucleated body cells
J) special types of immune cells

Question 45

Match each sentence with the most appropriate choice:

-Bone marrow

A) nonspecific response
B) specific response
C) T-cell
D) B-cell
E) IgE
F) Helper T-cells
G) T-cell growth factor
H) HIV
I) virtually all nucleated body cells
J) special types of immune cells

Question 46

Match each sentence with the most appropriate choice:

-Allergy

A) nonspecific response
B) specific response
C) T-cell
D) B-cell
E) IgE
F) Helper T-cells
G) T-cell growth factor
H) HIV
I) virtually all nucleated body cells
J) special types of immune cells

Question 47

Match each sentence with the most appropriate choice:

-Cytokines

A) nonspecific response
B) specific response
C) T-cell
D) B-cell
E) IgE
F) Helper T-cells
G) T-cell growth factor
H) HIV
I) virtually all nucleated body cells
J) special types of immune cells

Question 48

Match each sentence with the most appropriate choice:

-Interleukin-2

A) nonspecific response
B) specific response
C) T-cell
D) B-cell
E) IgE
F) Helper T-cells
G) T-cell growth factor
H) HIV
I) virtually all nucleated body cells
J) special types of immune cells

Question 49

Match each sentence with the most appropriate choice:

-AIDS

A) nonspecific response
B) specific response
C) T-cell
D) B-cell
E) IgE
F) Helper T-cells
G) T-cell growth factor
H) HIV
I) virtually all nucleated body cells
J) special types of immune cells

Question 50

Match each sentence with the most appropriate choice:

-Class I MHC glycoproteins

A) nonspecific response
B) specific response
C) T-cell
D) B-cell
E) IgE
F) Helper T-cells
G) T-cell growth factor
H) HIV
I) virtually all nucleated body cells
J) special types of immune cells

Question 51

Match each sentence with the most appropriate choice:

-Class II MHC glycoproteins

A) nonspecific response
B) specific response
C) T-cell
D) B-cell
E) IgE
F) Helper T-cells
G) T-cell growth factor
H) HIV
I) virtually all nucleated body cells
J) special types of immune cells

Question 52

Many systems use feedback loops as a regulatory mechanism. Discuss how the stress response involving the nervous system is involved in a negative feedback loop associated with immune function.

Question 53

Discuss at three examples of acquired immunity that occur in nonvertebrates and any similarities they have with vertebrate immunity.

Question 54

Compare and contrast the immunologic response that occurs as a result of natural exposure to a pathogen as opposed to exposure to a pathogen via vaccination. What effect does this have on long-term immunity?

Question 55

Compare and contrast the body's defenses to a viral infection when the virus is free in the extracellular fluid as opposed to after a virus has entered a cell.

Question 56

Describe how clonal selection works to give both primary and secondary immune responses.