Study Guide Test #4

The number of microorganisms required to produce a demonstrable infection in 50% of the test host population

Attachment of a microbe to another’s plasma membrane or other surface.

The ability of a microbe to cause disease by overcoming the defenses of the host

A carbohydrate-specific binding protein that projects from prokaryotic cells; used for adherence

The lethal dose for 50% of the inoculated hosts within a given period.

The avenue by which a pathogen gains access to the body – mucous membranes, skin, or parenteral route.

The degree of pathogenicity of a microorganism.

An attachment for a pathogen on a host cell.

A portal of entry for pathogens by deposition directly into tissues beneath the skin and mucous membranes

The most frequently used portal of entry for
pathogens is the
A) skin.
B) parenteral route.
C) mucous membranes of the respiratory tract.
D) All of these portals are used equally.
E) mucous membranes of the gastrointestinal tract.

The ID50 is
A) the dose that will kill 50 percent of the test population.
B) the dose that will cause an infection in 50
C) the dose that will kill some of the test population.
D) the dose that will cause an infection in some of the test population.
percent of the test population.
E) a measure of pathogenicity.

A bacterial outer membrane protein (gram -) that increases the attachment to and penetration of host cells and causes the bacterial colonies to be opaque. (cell wall component)

An outer, viscous covering on some bacteria composed of a polysaccharide or polypeptide (glycocalyx) that inhibits phagocytosis. (cell wall component)

An appendage on a bacterial cell used for attachment that increases virulence through improved penetration. (cell wall component)

A surface protein produced by Salmonella typhimurium and Escherichia coli that rearranges nearby actin filaments in the cytoskeleton of a host cell and increases host cell penetration. (host cell penetration)

A heat and acid resistant protein of streptococcal cell walls and fibrils that increases virulence through improved penetration. (cell wall component)

Long-chained, branched fatty acids that are characteristic of members of the genus Mycobacterium that increases virulence through resistance of phagocytosis. (cell wall component)

A bacterial enzyme that causes blood plasma to clot and increases virulence by protecting the bacteria cells from host defenses. (exoenzyme)

An enzyme secreted by certain bacteria that hydolyzes hyaluronic acid (connective tissue) and helps spread microorganisms from their initial site of infection. (exoenzyme)

A bacterial enzyme that breaks down fibrin (blood clots) that are formed to isolate an infection (streptokinase). (exoenzyme)

An enzyme that hydrolyzes collagen facilitating the spread of an infection through connective tissue. (exoenzyme)

Changes in the surface antigens that occur in a microbial population allowing the microbes to escape detection by the hosts immune system.

Which of the following statements is FALSE?
A) Kinase destroys fibrin clots.
B) Coagulase destroys blood clots.
C) Hyaluronidase breaks down substances
D) Leukocidins destroy neutrophils.
E) Hemolysins lyse red blood cells.
between cells.

The presence of toxins in the blood

The capacity of a microorganism to produce a toxin.

Any poisonous substances produced by a microorganism

A condition resulting from the ingestion of a microbially produced toxin.

Part of the outer portion of the cell wall of most gram-negative bacteria; released upon the destruction of the cell

The lipid portion of LPS that is the actual endotoxin found in the cell wall of most gram-negative bacteria. (endotoxin)

Excreted bacterial proteins that bind and accumulate iron for use by bacteria

A protein toxin released from living, mostly gram-positive bacterial cells

Bacterial exotoxins consisting of two polypeptides; the A part is an enzyme and the B part is a binding component. (exotoxin)

Substances produced by some bacteria that can destroy neutrophils and macrophages. (exotoxin)

An enzyme that lyses red blood cells.(exotoxin)

A sudden drop in blood pressure caused by bacterial toxins in the blood

An antigen that activates many different T cells, thereby eliciting a large immune response. (exotoxin)

Endotoxins are
A) A-B toxins.
B) molecules that bind nerve cells.
C) excreted from the cell.
D) part of the gram-negative cell wall.
E) associated with gram-positive bacteria

Symptoms of intense inflammation and shock
occur in some gram-positive bacterial infections
due to
A) lipid A.
B) erythrogenic toxin.
C) A-B toxins.
D) superantigens.
E) membrane-disrupting toxins.

The route by which a pathogen leaves the body.

A visible effect on a host cell, caused by a virus, that may result in host cell damage or death.

A carcinogenic toxin produced by Aspergillus

A toxin produced by a fungus.

A neurotixin produced by some dinoflagellates

Cytopathic effects are changes in host cells due to
A) fungal infections.
B) viral infections.
C) bacterial infections.
D) protozoan infections.
E) helminthic infections.

Transmembrane protein of immune cells that recognizes pathogens and activates an immune response directed against those pathogens

Signaling proteins induced by TLRs in defensive cells that regulate the intensity of an immune response.

Host defenses that afford protection against any kind of pathogen (non-specific)

Molecules and their patterns found on pathogens that are not found on self cells

The ability, obtained during the life of the individual, to produce specific antibodies and T cells that detect and eliminate certain pathogens (specific).

The ability to ward off disease caused by microbes or their products through innate and adaptive mechanisms and to protect against environmental agents such as pollen, chemicals, and animal dander.

Lack of resistance to a disease

Innate immunity
A) involves T cells and B cells.
B) involves a memory component.
C) is slower than adaptive immunity in responding to pathogens.
D) is nonspecific and present at birth.
E) provides increased susceptibility to disease.

An enzyme in perspiration that is capable of breaking down peptidoclycan cell walls of bacteria.

The outer and thinner portion of the skin that is in direct contact with the external environment

Ciliated mucosal cells of the lower respiratory tract that move inhaled particles away from the lungs.

Oily substance produced by the sebaceous glands that forms a protective film over the surface of the skin.

A group of structures that protects eyes by manufacturing and draining tears

The inner and thicker portion of the skin that is composed of connective tissue

Membranes that line the body openings, including the intestinal tract, open to the exterior and fill with mucous that traps pathogens and prevents entry

A protein found in the epidermis, hair, and nails that creates a protective layer in the dead epidermal cells of the epidermis

All of the following protect the skin and mucous
membranes from infection EXCEPT
A) HCl.
B) the "ciliary escalator."
C) multiple layers of cells.
D) saliva.
E) tears.

Microbes inoculated in a host to occupy a niche and prevent growth of pathogens.

The formation of blood cells in the red bone marrow by stem cells.

The microorganisms that colonize a host without causing disease.

The white bloods cells that are a formed element of the blood.

A highly phagocytic granulocyte; also called a polymorphonuclear leukocyte (PMN) or polymorph; leave the blood, enter infected tissue, and destroy microbes and foreign particles

A leukocyte with visible granules in the cytoplasm when viewed through a light microscope; includes neutrophils, basophils, and eosinophils.

A granulocyte that readily takes up basic dye and is not phagocytic; has receptors for IgEFc regions; important in inflammation and allergic response

A granulocyte whose granules take up the stain eosin; somewhat phagocytic and leave the blood; produce toxic proteins against certain parasites, such as helminths.

A leukocyte precursor cell that leaves circulating blood, enters body tissues, and matures into macrophages

A leukocyte without visible granules in the cytoplasm when viewed through a light microscope; includes monocytes and lymphocytes

A type of antigen presenting cell characterized by long finger-like extensions; found in lymphatic tissue and skin.

A leukocyte involved in specific immune responses.

A lymphoid cell that destroys tumor cells and virus-infected cells; release perforin and granzymesto attack cells

Which of the following is involved in resistance to parasitic
helminths?
A) basophils
B) neutrophils
C) monocytes
D) eosinophils
E) lymphocytes

Macrophages arise from which of the following?
A) neutrophils
B) lymphocytes
C) eosinophils
D) basophils
E) monocytes

The ingestion of microorganisms or other large particles by eukaryotic cells.

A macrophage that is located in a certain organ or tissue

Consists of a fluid called the lymph, vessels called the lymphatic vessels, a number of structures and organs (thymus and spleen) containing lymphoid tissue, and red bone marrow, where stem cells develop into blood cells, including lymphocytes.

A cell capable of engulfing and digesting microorganisms or other large particles that are harmful to the body.

A macrophage that leaves the blood and migrates to infected tissues.

During the digestion stage of phagocytosis; created from the fusion of the phagosome and a lysosome inside of the macrophage where digestive enzyme degrade the microbe and then discharge the residual body waste outside of the cell.

During the ingestion stage of phagocytosis; pseudopods meet and fuse to form an acid containing food vacuole (phagocytic vesicle) that around the ingested microbe

During the chemotaxis and adherence stage of phagocytosis; attachment of a phagocyte to another’s plasma membrane or surface.

During the ingestion stage of phagocytosis; cellular extensions created by phagocytes that engulf the microorganism.

During the chemotaxis and adherence stage of phagocytosis; movements of phagocytes toward a microorganism in response to a chemical released by the microorganism.

The late stage of fever characterized by vasodilation and sweating

A host response to tissue damage characterized by redness, pain, heat, and swelling; and sometimes loss of function.

During the early stages of inflammation, these serum proteins increase in concentration by at least 25%.

An abnormally high blood temperature caused by cytokines that reset the hypothalamic thermostat to a higher temperature.

Dilation or enlargement of blood vessels in response to infection as part of the inflammation process

During the vasodilation and increased permeability stage of inflammationthis abnormal accumulation of interstitial fluid in tissues occurs causing swelling.

The final stage of inflammation in which tissues replaced dead or damaged cells

During the vasodilation and increased permeability stage of inflammationthis substance is released by tissue cells and causes vasodilation, capillary permeability, and smooth muscle contraction

During the phagocyte migration and phagocytosis stage of inflammation phagocytes begin to squeeze between the endothelial cells of the blood vessel through this process to reach the damaged area

During the vasodilation and increased permeability stage of inflammationan accumulation of dead phagocytes, dead bacterial cells, and fluid that occurs in a cavity formed by the breakdown of body tissues

During the phagocyte migration and phagocytosis stage of inflammation this process occurs that allows phagocytes to stick to the lining of blood vessels

All of the following occur during inflammation. What is the
first step?
A) diapedesis
B) repair
C) margination
D) phagocyte migration
E) vasodilation

A chill is a sign that
A) body temperature is falling.
B) body temperature is rising.
C) the metabolic rate is decreasing.
D) blood vessels are dilating.
E) body temperature is not changing.

Margination refers to
A) the movement of phagocytes through walls of blood
vessels.
B) the chemotactic response of phagocytes.
C) dilation of blood vessels.
D) the adherence of phagocytes to microorganisms.
E) adherence of phagocytes to the lining of blood vessels.

Short peptides made by animal cells that have a broad spectrum of antimicrobial activities.

A specific group of cytokines produced by animal cells in response to a viral infection.

A protein made in response to interferon that blocks viral multiplication.

The complement pathway that does not involve antibodies but instead is activated when there is contact between certain complement proteins and a pathogen causing direct activation of C3 which participates in inflammation, opsonization, and cytolysis

The complement pathway that is initiated when antibodies bind to antigens activating C1 which in turn activates C2 and C4. C2 and C4 activate C3 that participates in inflammation, opsonization, and cytolysis

Over 30 proteins produced in the liver that circulate in the blood serum and within the tissues throughout the body that ”completes” or assists the immune system by destroying microbes through cytolysis, opsonization, and inflammation

The complement pathway that is activated when macrophages release cytokines that stimulate the liver to produce lectins. Lectins can activate C2 and C4 like the classical pathway which results in activation of C3 and an increase in inflammation,
opsonization, and cytolysis

Immune adherence that promotes the attachment of a phagocyte to a microbe

Complement proteins C5-C9, which together makes lesions in cell membranes that lead to cell death through cytolysis

The complement protein cascade is the same for the
classical pathway, alternative pathway, and lectin pathway
after the point in the cascade where the activation of
________ takes place.
A) C3
B) C6
C) C1
D) C5
E) C2

Which of the following is an effect of opsonization?
A) cytolysis
B) inflammation
C) increased adherence of phagocytes to microorganisms
D) increased diapedesis of phagocytes
E) increased margination of phagocytes

The first time the adaptive immune system meets and combats a particular foreign substance.

The ability obtained during the life of the individual , to produce specific antibodies and T Cells.

Later interactions between the adaptive immune system and a cell or substance that are faster and more effective as a result of cellular memory

Molecules on T cells that recognize antigens

A type of lymphocyte; differentiates into antibody-secreting plasma cells and memory cells.

An immune response that involves T cells binding to antigens presented on antigenpresenting cells; T cells then differentiate into several types of effector T cells

A type of lymphocyte, which develops from stem cells processed in the thymus gland, that is responsible for cell-mediated immunity

Immunity produced by antibodies dissolved in body fluids, mediated by B cells; also called antibody-mediated immunity

A protein produced by the body in response to an antigen, and capable of combining specifically with an antigen

Which of the following is NOT a characteristic of cellular
immunity?
A) T cells react with antigens.
B) B cells make antibodies.
C) It can inhibit the immune response
D) Cells are processed in the thymus gland.
E) The cells originate in bone marrow.

The first class of antibodies to appear after exposure to an antigen; pentamer structure that remains in the circulation

The class of antibodies found on the surface of B cells

The most abundant class (80%) of antibodies in serum; fix complement; enhance phagocytosis; participates in inflammation; protects against circulating viruses and bacteria; and provide fetal immunity.

The class of antibodies found in secretions like mucous membrane secretions and breast milk.

The class of antibodies involved in hypersensitivities like allergies

A protein (antibody) formed in response to an antigen and can react with that antigen

A specific region on the surface of an antigen against which antibodies are formed; also called an antigenic determinant.

A Y-shaped bivalent antibody with four protein chains: two identical light chains and two identical heavy chains

The genes that code for histocompatibility antigens; also known as human leukocyte antigen complex.

Any substance that causes antibody formation; from antibody generators; also called an immunogen.

A substance of low molecular weight that does not cause the formation of antibodies by itself but does so when combined with a carrier molecule

The class of MHC molecules that exist on the surface of antigen-presenting molecules (APCs) including B cells

The class of MHC found on the plasma membranes of mammalian nucleated cells that identify “self”.

Which of the following is the best definition of epitope?
A) specific regions on antigens that interact with antibodies
B) specific regions on antigens that interact with MHC class molecules
C) specific regions on antigens that interact with T-cell receptors
D) specific regions on antigens that interact with perforins
E) specific regions on antigens that interact with haptens

The antibodies found in mucus, saliva, and tears are
A) IgA.
B) IgE.
C) IgD.
D) IgG.
E) IgM.

The elimination of B and T cells that react with self-antigens.

An antigen-antibody reaction that inactivates a bacterial exotoxin or virus.

The process of B cell differentiation into antibody producing plasma cells and long-lived memory cells for enhanced secondary response.

The killing of antibody coated cells by natural killer cells and leukocytes

When antibodies cause antigens to clump together

Antibody binding to antigens that enhances phagocytosis by phagocytes

An antigen that will stimulate the formation of antibodies without assistance of T Helper cells

An antigen that will stimulate the formation of antibodies only with the assistance of T Helper cells

A specialized T cell that often interacts with an antigen before B cells interact with the antigen

A lymphoid cell that destroys tumor cells and virus-infected cells but is antibody independent

Which of the following bacterial components would most
likely result in B cell stimulation by T-independent antigens?
A) pili
B) plasmid
C) ribosome
D) flagellum
E) capsule

Which of the following statements is NOT a possible
outcome of antigen-antibody reaction?
A) activation of complement
B) agglutination
C) ADCC
D) clonal deletion
E) opsonization

A macrophage that has increased phagocytic ability and other functions after exposure to mediators released by T cells after stimulation by antigens

Elimination of T cells that don’t recognize MHC molecules for an immune response

Cells in the gastrointestinal tract that take up and transfer antigens to lymphocytes in Peyer’s patches

Proteases that induce apoptosis.

T cells that combat autoimmunity by repressing other T cells

The natural programmed cell death of a cell; the residual fragments are disposed of by phagocytosis.

An activated T cell that kills cells presenting endogenous antigens. Bind to MHC Class I molecules and destroy virus infected cells

Protein that makes a pore in a target cell membrane, released by cytotoxic T lymphocytes.

T cells that recognize an antigen presented on the surface of a macrophage and activate the macrophage. Bind to MHC Class II molecules on B cells and APCs

A type of antigen-presenting cell for cellular immunity characterized by long finger-like extensions; found in lymphatic tissue and skin.

Thymic selection 2
A) activates B cells.
B) destroys MHC molecules.
C) destroys T cells that do not recognize self-molecules of MHC.
D) destroys CD4+ cells that attack self.
E) destroys B cells that make antibodies against self.

Which of the following destroys virus-infected cells?
A) B cells
B) TH
C) Treg
D) dendritic cells
E) CTL

A rapid rise in antibody titer following exposure to an antigen after the primary response to that antigen; also called anamnestic response or secondary response.

The amount of antibody in serum

Antibody production in response to first contact with an antigen

The natural transfer of humoral antibodies, for example, transplacental transfer.

The production of antibodies by the body in response to a vaccination

The transfer of humoral antibodies formed by one individual to a susceptible individual by the injection of antiserum

Antibody production in response to an infectious disease

The branch of immunology that studies blood serum and antigen-antibody reaction in vitro.

A blood-derived fluid containing antibodies