final 51-100

1.

1 point

What is a phagolysosome?

When a phagocyte starts to produce lysosomes

When a phagosome fuses with several lysosomes to digest a pathogen

When a defensin starts producing hydrogen peroxide

A structure formed during the respiratory burst following phagocytosis

2.

1 point

Which one of the following does not apply to plasma cells?

They carry out their functions by producing cytokines.

They secrete antibodies.

They are derived from B cells.

They are effector cells

3.

1 point

Which one of the following is not a toxic substance within the phagolysosome?

Nitric oxide (NO)

Acid hydrolases

Chemokines

Superoxide anion (O2-)

4.

1 point

Which of the following cells are leukocytes?

Platelets

Erythrocytes

Neutrophils

Thrombocytes

5.

1 point

Innate immunity is the form of immunity that

requires T and B lymphocytes

occurs in the thymus

takes place only in the blood.

responds quickly to many common microbial features but not to host features.

6.

1 point

All of the following are true about a low to moderate fever except

it increases the body’s rate of tissue repair.

it may be beneficial in immune defense.

it may inhibit the rapid growth of pathogens.

it may cause convulsion and death.

7.

1 point

Pus is often found in infections. It is composed of

dead and dying neutrophils and damaged tissues.

fibrin clots.

fluid leaking out of the blood vessels.

the digested material expelled from the phagocyte.

8.

1 point

Opsonins may be described as

short antibacterial peptides.

types of bacterial exotoxins that destroy white blood cells.

types of white blood cells that are especially efficient phagocytes.

substances that enhance the efficiency of phagocytosis.

9.

1 point

Chemical barriers to infection include all of the following except

mucus

defensins.

stomach acid.

low pH of vaginal secretions.

10.

1 point

A chemical circulating in the blood that causes a fever to develop is called a

Perforin.

Pyrogen

Pyogen

Histamine.

11.

1 point

Which of the following protects against colonization of pathogens by taking up space and nutrients on the skin and mucosa?

Sebum

Nonpathogenic microbes that live on those surfaces

Phagocytes

Mast cells

12.

1 point

. Which one of the following is not an effect of complement activation?

Lysis of pathogens

Production of substances that trigger an inflammatory response

Opsonization

Enhancement of T cell function through production of cytokines

13.

1 point

Locations in the body where mature immune cells interact with pathogens are likely to be in the

bone marrow where red cells are formed.

membranes of the brain.

thymus gland.

lymph nodes and spleen.

14.

1 point

Which cells can develop into antibody producing cells?

B lymphocytes

T lymphocytes

Dendritic cells

Macrophages

15.

1 point

Which of the following is not a lymphocyte?

B cells

Monocytes

T cells

NK cells

16.

1 point

Which of the following are mechanical barriers in the body's first line of defense?

Normal microbiota like Lactobacillus lining the vaginal tract

Mucus lining the upper respiratory tract

Intact skin

Lysozymes in tears

17.

1 point

NK cells secrete two enzymes that attack foreign, virus infected or cancerous cells. What are they?

Perforin and granzymes

Heparin and granzymes

Pyrogen and lysozymes

Histamine and lysozymes

18.

1 point

A nonspecific leukocyte that destroys tumor cells and cells that are infected with viruses is the

NK cell.

neutrophil

monocyte

basophil.

19.

1 point

The theory called clonal selection specifies that

T cells are involved in the process by which antibodies are produced against epitopes.

exposure to an antigen activates only those T- and B-cells with receptors recognizing specific epitopes on the antigen.

the activation of Tcells produces antibodies that recognize epitopes.

B cellsprovide resistance through direct cell-to-cell contact with and lysis of infected or otherwise abnormal cells.

20.

1 point

Which of the following is not one of the four cardinal signs of inflammation?

Redness

Pain

swelling

bleeding

21.

1 point

Lysozyme acts on bacteria by

stimulating interferon production.

inhibiting protein synthesis in all bacteria.

destroying the cell wall of gram-positive bacteria.

interfering with the motility of bacteria.

22.

1 point

The theory of specific immunologic tolerance suggests that

antigens tolerate self-destruction by phagocytes.

a person’s own cells do not stimulate an immune response.

antibodies react specifically with immunologic substances.

antibodies are produced by only one clone of cells.

23.

1 point

Which one of the following are not immunogenic?

Pilus protein

Components of bacterial capsules

Flagella proteins

Haptens

24.

1 point

Haptens are poor stimulators of immunity because haptens may be

easily digested by the phagocytes.

inability to perform cross-linking.

unable to locate the proper B cell.

too small to recognize the antigens at the receptor sites.

25.

1 point

All the following apply to the body's white blood cells except

they are produced in the bone marrow.

they carry oxygen to the tissues.

they have no pigment in their cytoplasm, so appear grayish when unstained.

D. they include cells that function in innate immunity and cells that function in acquired immunity.

26.

1 point

Which of the following leukocytes are involved in acquired immunity?

Monocytes and macrophages

Neutrophils and NK cells

B lymphocytes and T lymphocytes

Basophils and eosinophils

27.

1 point

Which of the following cells are agranulocytes?

Neutrophils

Basophils

Eosinophils

Monocytes

28.

1 point

The immune response to intracellular pathogens is controlled and regulated by

T cells.

B cells.

natural killer cells.

dendritic cells.

29.

1 point

All of the following are true about chemical defensins except

produced in the bone marrow.

found and produced on the skin surface.

produced by epithelial cells that line the respiratory, gastrointestinal and urogenital tracts.

produced by phagocytic cells.

30.

1 point

Which of the following is a primary lymphoid tissue?

Spleen

Appendix

Lymph nodes

Thymus

31.

1 point

The cells that have long, thin cytoplasmic extensions, are found in various body tissues and are very important in activation of lymphocytes are the

Dendritic cells.

Eosinophils.

T cells.

Neutrophils.

32.

1 point

Antigenic determinants are the parts of antigen molecules that

code for antibody molecules.

stimulate the immune system.

clot blood

stimulate phagocytosis.

33.

1 point

When Metchnikoff put a splinter into the body of a starfish larva, he saw that it was soon surrounded by wandering cells. He was observing a process that today is described as

phagocytosis.

escortation.

neutralization.

opsonization.

34.

1 point

Which of the following are secondary lymphoid tissues?

Lymph nodes

Appendix

Tonsils

All of the above are correct.

35.

1 point

The innate immune system recognizes pathogens by identifying PAMPS, unique microbial molecular sequences that are not found on host cells. The receptors on macrophages, dendritic cells and endothelial cells that bind to these PAMPS are called

opsonin receptors

chemokine receptors.

acute phase proteins

toll-like receptors.

36.

1 point

Which of the following is true about both macrophages and neutrophils?

Are phagocytes

Lack a nucleus

Have large granules in the cytoplasm

Have a life span of about 10 years

37.

1 point

The ability to mount an efficient secondary antibody response depends on

cross-linking of IgM antibodies.

high concentrations of IgA antibody.

memory T and B cells.

All the above are correct.

38.

1 point

A compound that digests the cell wall of gram positive bacteria is

bile.

interferon.

lysozyme.

stomach acid.

39.

1 point

Natural killer (NK) cells can be described by all of the following except

NK cells have special receptors for target cells on the surface of their membrane.

NK cells secrete several cytokines that trigger responses from macrophages and other cells.

NK cells are phagocytes that rely on Class I MHC proteins to recognize the body’s cells.

NK cells recognize the body’s cells and do not attack them.

40.

1 point

The function of the formation of a fibrin clot during an inflammatory response to a bacterial infection is to

enhance diapedesis.

wall off the infecting bacteria to prevent their spread.

poison the bacteria

signal a response from specific lymphocytes.

41.

1 point

Which of the following blood cells has the shortest life-span?

Monocytes

Macrophages

Neutrophils

Erythrocytes

42.

1 point

The theory of clonal selection refers to the

activation of naïve lymphocytes with receptors for a certain epitope

conversion of plasma cell to B lymphocyte.

activity of cytotoxic and helper T cells.

reversion of clones of B lymphocytes to clones of selected T lymphocytes.

43.

1 point

Chemokines are cytokines that

activate the acquired immune response.

stimulate neutrophils to migrate to the site of an infection

induce an antiviral state in a cell

All the above are correct.

44.

1 point

Neutrophils are those leukocytes that function

in the production of antibodies.

as manufacturers of clotting agents.

as phagocytes in body resistance

to neutralize acidic environments

45.

1 point

Which of the following is the function of secondary lymphoid tissues?

Sites where immune cells form

Returns body fluids to the circulatory system

Responsible for the production of blood cells.

Where mature immune cells interact with pathogens and carry out the acquired immune response

46.

1 point

All of the following statements are true about complement except

it may be activated by three different pathways.

it can lead to formation of the membrane attack complex.

it is a single protein that circulates in the blood.

it contributes to enhancement of the inflammatory response and phagocytosis.

47.

1 point

Which of the following organs is part of the mucosa-associated lymphoid tissues (MALT)?

Peyer patches

Lymph nodes

Spleen

All of the above are correct

48.

1 point

At the site of tissue damage and/or infection, tissue macrophages secrete cytokines that induce

vasodilation and increased vascular permeability, allowing more cells and fluid into the area.

septic shock in the area.

destruction of cells in the area so that the infection does not spread.

bleeding to increase the blood in the area.

49.

1 point

The blood cell that contains cytotoxic granules that are particularly useful in killing multicellular parasites is the

natural killer cells.

neutrophil.

monocyte.

eosinophil.

50.

1 point

The cell-surface receptor on a B cell is a(n)

antibody molecule.

antigen.

cluster of haptens.

molecule of polysaccharide.