MCB2000 Practice Exam 4

Innate immunity
a) involves a memory component.
b) provides increased susceptibility to disease.
c) is nonspecific and present at birth.
d) involves T cells and B cells.
e) is slower than adaptive immunity in responding to pathogens.

Ingestion of certain lactic acid bacteria (LABs) has been shown to be beneficial for function and health of the intestinal tract.
T/F

Which of the following antimicrobial agents is recommended for use against fungal infections?
a) bacitracin
b) polymyxin
c) amphotericin B
d) cephalosporin
e) penicillin

Innate immunity includes all of the following EXCEPT
a) production of antibody.
b) activation of complement.
c) production of interferon.
d) inflammation.
e) phagocytosis.

Which of the following is an effect of opsonization?
a) increased margination of phagocytes
b) cytolysis
c) inflammation
d) increased adherence of phagocytes to microorganisms
e) increased diapedesis of phagocytes

The function of the "ciliary escalator" is to
a) remove microorganisms from the lower respiratory tract.
b) trap microorganisms in mucus in the upper respiratory tract.
c) propel inhaled dust and microorganisms toward the mouth, away from the lower respiratory tract.
d) remove microorganisms from the gastrointestinal tract.
e) trap inhaled dust and microorganisms in mucus and propel it away from the lower respiratory tract.

Use of antibiotics in animal feed leads to antibiotic-resistant bacteria because
a) the few surviving bacteria that are affected by the antibiotics develop immunity to the antibiotics, which they pass on to their progeny.
b) the antibiotics persist in soil and water.
c) bacteria from other animals replace those killed by the antibiotics.
d) the antibiotics cause new mutations to occur in the surviving bacteria, which results in resistance to antibiotics.
e) the antibiotics kill susceptible bacteria, but the few that are naturally resistant live and reproduce, and their progeny repopulate the host animal.

Adjuvants such as aluminum salts are used as additives in vaccines to enhance immune responses.
T/F

What type of immunity results from transfer of antibodies from one individual to a susceptible individual by means of injection?
a) innate immunity
b) naturally acquired active immunity
c) naturally acquired passive immunity
d) artificially acquired active immunity
e) artificially acquired passive immunity

Which of the following is involved in resistance to parasitic helminths?
a) monocytes
b) basophils
c) neutrophils
d) eosinophils
e) lymphocytes

Which non-specific defense mechanism is mismatched with its associated body structure or body fluid?
a) cerumen and sebum ear
b) lysozyme tears and saliva
c) very acidic pH stomach
d) keratin and tightly packed cells skin
e) mucociliary escalator intestines

Which of the following destroys virus-infected cells?
a) TH
b) CTL
c) B cells
d) Treg
e) dendritic cells

All of the following pertain to fever EXCEPT that it
a) can be initiated by specific types of pathogens.
b) accelerates microbial growth by increasing iron absorption from the digestive tract.
c) intensifies the effect of antiviral interferons.
d) is caused by interleukin-1 and TNF-alpha coming into contact with the hypothalamus.
e) stimulates T lymphocyte activity.

The classical pathway for complement activation is initiated by
a) factors released from damaged tissues.
b) antigen-antibody reactions.
c) factors released from phagocytes.
d) lipid-carbohydrate complexes and C3.
e) C5-C9.

What type of immunity results from recovery from mumps?
a) innate immunity
b) naturally acquired active immunity
c) naturally acquired passive immunity
d) artificially acquired active immunity
e) artificially acquired passive immunity

Hemolytic disease of the newborn can result from an
a) Rh- mother and an A fetus.
b) Rh+ mother with an Rh- fetus.
c) AB mother with a B fetus.
d) AB mother with an O fetus.
e) Rh- mother with an Rh+ fetus.

In a vaccine preparation, the term "attenuated" means that the agent does NOT replicate.
T/F

All of the following are generally used in vaccines EXCEPT
a) inactivated viruses.
b) parts of bacterial cells.
c) live, attenuated viruses.
d) toxoids.
e) antibodies.

All of the following protect the skin and mucous membranes from infection EXCEPT
a) tears.
b) saliva.
c) HCl.
d) the "ciliary escalator."
e) multiple layers of cells.

Each of the following provides protection from phagocytic digestion EXCEPT
a) M protein.
b) biofilms.
c) capsules.
d) formation of phagolysosomes.
e) leukocidins.

Which of the following statements about drug resistance is FALSE?
a) It may be due to decreased uptake of a drug.
b) It may be transferred from one bacterium to another during conjugation.
c) It is found only in gram-negative bacteria.
d) It may be due to enzymes that degrade some antibiotics.
e) It may be carried on a plasmid.

All of the following are reasons why an HIV vaccine has not been developed EXCEPT
a) HIV has a high mutation rate so one vaccination would not be effective to treat the world-wide pandemic.
b) there is no known animal model of natural immunity for HIV infection.
c) use of a weakened virus would potentially transmit the infection.
d) small, inexpensive animals which could be used for HIV vaccine research are not available.
e) vaccines are not effective against viral infections.

Penicillin was considered a "miracle drug" for all of the following reasons EXCEPT
a) it kills bacteria.
b) it has selective toxicity.
c) it was the first antibiotic.
d) it does not affect eukaryotic cells.
e) it inhibits gram-positive cell wall synthesis.

Rheumatoid arthritis is due to deposition of
a) IgG and IgA complexes in joints.
b) complement in joints.
c) complexes of IgM and IgG and also complement in joints.
d) IgA antibodies in joints.
e) IgD and IgE complexes in joints.

The BOD is a measurement of the amount of bacteria present before and after the sewage treatment process.
T/F

Immunodeficiencies are a result of all of the following EXCEPT
a) autoimmune diseases.
b) DiGeorge syndrome.
c) Hodgkin's disease.
d) cyclosporine.
e) HIV infection.

Desensitization involves injection of
a) antigens.
b) antihistamine.
c) IgE antibodies.
d) histamine.
e) IgG antibodies.

Drug resistance occurs
a) when antibiotics are used indiscriminately.
b) against antibiotics and not against synthetic chemotherapeutic agents.
c) when antibiotics are taken after the symptoms disappear.
d) because bacteria are normal microbiota.
e) All of the answers are correct.

In addition to IgG, the antibodies that can fix complement are
a) IgM.
b) IgD.
c) IgA.
d) IgE.
e) None of the answers is correct.

Complement proteins in their intact and unactivated form act as opsonins by binding to microorganisms and promoting phagocytosis.
T/F

The process of desensitization to prevent allergies involves the injection of increasing amounts of
a) IgG.
b) antihistamine.
c) RhoGAM.
d) antigen.
e) IgE.

What type of immunity results from vaccination?
a) innate immunity
b) naturally acquired active immunity
c) naturally acquired passive immunity
d) artificially acquired active immunity
e) artificially acquired passive immunity

Which item is from the patient in a direct ELISA test?
a) antibodies against the antigen
b) antihuman immune serum
c) substrate for the enzyme
d) antigen

Microorganisms that are members of the normal microbiota are also known to cause disease.
T/F

The most abundant class of antibodies in serum is
a) IgE.
b) IgG.
c) IgM.
d) IgA.
e) IgD.

The dermis is composed of connective tissue and serves the primary purpose of providing direct protection from the external environment.
T/F

Phagocytes utilize all of the following to optimize interaction with (getting to and getting hold of) microorganisms EXCEPT
a) chemotaxis.
b) opsonization.
c) trapping a bacterium against a rough surface.
d) lysozyme.
e) complement.

Allergic contact dermatitis is due to
a) IgG antibodies.
b) activated macrophages.
c) IgE antibodies.
d) IgM antibodies.
e) sensitized T cells.

A patient shows the presence of antibodies against diphtheria toxin. Which of the following statements is FALSE?
a) The patient may have been vaccinated.
b) The patient may have the disease.
c) The patient was near someone who had the disease.
d) A recent transfusion may have passively introduced the antibodies.
e) The patient may have had the disease and has recovered.

The symptoms of an immune complex reaction are due to
a) antibodies against self.
b) cytokines.
c) destruction of the antigen.
d) phagocytosis.
e) complement activation.

All of the following are considered examples of type I hypersensitivity EXCEPT
a) asthma.
b) transplant rejections.
c) dust allergies.
d) penicillin allergic reactions.
e) pollen allergies.

Which one of the following processes in sewage treatment requires bacterial metabolism?
a) primary treatment
b) sedimentation
c) removal of BOD
d) chlorination
e) None of the answers is correct.

The specificity of an antibody is due to
a) its valence.
b) the H chains.
c) the constant portions of the H and L chains.
d) the variable portions of the H and L chains.
e) the L chains.

Which of the following WBCs are NOT lymphocytes?
a) helper T cells
b) B cells
c) cytotoxic T cells
d) M cells
e) NK cells

Which wastewater treatment process is responsible for removal of most of the BOD in sewage?
a) anaerobic sludge digestion
b) primary sewage treatment
c) secondary sewage treatment
d) tertiary sewage treatment
e) water treatment

When an antibody binds to a toxin, the resulting action is referred to as
a) agglutination.
b) ADCC.
c) apoptosis.
d) opsonization.
e) neutralization.

Drinking water supplies are routinely tested for the presence of
a) Giardia.
b) Cryptosporidium.
c) Vibrio.
d) fecal coliforms.
e) fecal viruses.

A hypersensitivity reaction refers to immune responses to antigens beyond what would be normal.
T/F

All of the following are habitats for extremophiles EXCEPT
a) the topmost portions of the Atlantic Ocean.
b) a salt-evaporating pond.
c) 100°C water.
d) an acid mine wash.
e) inside rock.

Which of the following reactions is performed by yeast in wine-making?
a) carbon dioxide → sucrose
b) ethanol → acetic acid
c) malic acid → lactic acid
d) sugar → ethanol
e) sugar → CO2 + H2O