final lecture exam Flashcards
Compromised hosts are always suffering from a suppressed immune system T/F?
False
A host is not considered diseased until an infection changes ones state of health T/F?
True
Urinary tract infections are the most common forms of nosocomial infections T/F?
True
Reservoirs of infections are always animate objects T/F?
False
Which of the following statements is true?
A) a parasite is not in symbiosis with its host
B) Members of a symbiotic relationship cannot live without each other
C) At least one member must benefit in a symbiotic relationship
C) at least one member must benefit in a symbiotic relationship
Which of the following diseases is not spread by droplet infection? A) the common cold B) botulism C) Measles D) diphtheria E) tuberculosis
B) botulism
Which of the following is NOT a communicable disease? A) tetanus B) tuberculosis C) AIDS D) malaria
A) tetanus
Which of the following can contribute to postoperative infection?
A) normal microbiota on the operating room staff
B) antibiotic resistance
C) Using syringes more than once
D) Errors in aseptic technique
E) all of the answers are correct
E) all answers are correct
In general the LD50 for exotoxins is much greater than the LD50 for endotoxins, T/F
F
The M protein enhances the virulence of streptococcus by preventing phagocytosis T/F?
True
Most symptoms of endotoxins can be treated with administration of anti-endotoxin antibodies, T/F?
False
Infections with some viruses may induce chromosomal changes that alter the growth properties of host cells T/F?
True
All of the following contribute to a pathogen's invasiveness EXCEPT... A) capsules B) Coagulases C) Cell wall components D) Hyaluronidase E) toxins
E) toxins
Endotoxins are .... A) molecules that bind nerve cells B) Part of the gram negative cell wall C) Associated with gram-positive bacteria D) A-B Toxins E) Excreted from the cell
B) part of the gram negative cell wall
Which of the following is NOT a membrane disrupting toxin? A) Hemolysins B) Streptolycin S C) Leukocidin D) A-B toxin E) Streptolycin O
D) a-b toxin
All of the following are examples of entry via parenteral route except A) injection B) bite C) skin cut D) Hair follicle E) surgery
D) hair follicle
Which of the following cytopathic effects is cytocidal? A) antigenic changes B) transformation C) Giant cells D) Release of enzymes from lysozomes E) Inclusion bodies
D) release of enzymes from lysosomes
Which of the following contributes to the virulence of a pathogen?
A) evasion of host defenses
B) numbers of microorganisms that gain access to a host
C) toxin production
D) Numbers of microorganisms that gain access to a host, evasion of host defenses and toxin production
D) Numbers of microorganisms that gain access to a host, evasion of host defenses and toxin production
Microorganisms that are members of the normal microbiota are also known to cause disease T/F?
True
The inflammatory response can only be triggered by an infection T/F?
False
Complement proteins act as opsonins by binding to microorganisms and promoting phagocytosis T/F?
False
An example of a TLR would be peptidoglycan found in the cell wall of gram positive bacteria T/F?
True
Which of the following exhibits the highest phagocytic activity? A) macrophages B) erythrocytes C) Neutrophils D) Eosinophils
A) macrophages
A differential cell count is used to determine each of the following EXCEPT:
A) numbers of each type of white blood cell
B) The total number of white blood cell
C) The number of red blood cells
D) Leukopenia
E) Leukocytosis
C) the number of red blood cells
Each of the following is an effect of complement activation except: A) bacterial cell lysis B) interference with viral replication C) Opsonization D) Increased phagocytic activities
B) interference with viral replication`
Each of the following provides protection from phagocytic digestion EXCEPT: A) formation of phagolysosomes B) Biofilms C) Leukocidins D) M protein E) Capsules
A) formation of phagolysosomes
Innate immunity includes all of the following EXCEPT A) inflammation B) production of antibody C) Activation of compliment D) Phagocytosis E) Production of interferon
B) production of antibody
After ingesting a pathogen, lysosomal enzymes produces all of the following EXCEPT A) O2- B) H2O2 C) OH D) complement E) HOCl
D) complement
Granzymes kills cells by causing significant leakage of cellular contents T/F?
False
Cytokines are protein-based chemical messengers that allow for communication between cells of the immune system T/F?
True
The variable region of the antibody is responsible for the significant diversity of antigen targets T/F?
False
Memory cells do not require B cell receptors T/F?
False
When an antibody binds to a toxin, the resulting action is referred to as __________.
Neutralization
CD4+ T cells are activated by _______
Interaction between CD4+ and MHC II
Which of the following statements is false?
A) the constant region of a heavy chain is the same for all antibodies
B) The Fc region can attach to a host cell
C) The variable region of a light chain contributes to antigen binding
D) The variable region of a heavy chain contributes to antigen binding
A) the constant region of a heavy chain is the same for all antibodies
Which of the following WBCs are NOT lymphocytes A) NK cells B) Helper T cells C) B cells D) M cells E) Cytotoxic T cells
D) M cells
Cytokines released by Th1 cells-
Activate macrophages
Thymic selection -
Destroys T cells that do not recognize self molecules of MHC
An injection of “naked” DNA into muscle cells to induce an immune response against the proteins encoded by the DNA is an example of a subunit vaccine. T/F
FALSE
Blood typing tests are examples of hemagglutination reactions. T/F?
True
The home pregnancy test kit is an example of a direct ELISA. T/F?
True
Agglutination tests use particulate antigens while precipitation tests use soluble antigens. T/F?
True
Patient's serum, influenza virus, and red blood cells are mixed in a tube. What happens if the patient has antibodies against influenza virus? a) Agglutination b) Complement fixation c) Hemagglutination D) hemagglutination-inhibition
D) hemagglutination-inhibition
In an agglutination test, eight serial dilutions to determine antibody titer were set up. Tube #1 contained a 1:2 dilution; tube
#2, a 1:4, etc. If tube #6 is the last tube showing agglutination, what is the antibody titer?
a) 32 b) 6 c) 64 d) 1:32 e) 1:6
C) 64
A reaction between an antibody and soluble antigen-forming lattices is called a(n)
a) Agglutination reaction.
b) Complement fixation.
c) Immunofluorescence.
d) Precipitation reaction.
e) Neutralization reaction.
A) agglutination reaction
A test used to detect anti-Rickettsia antibodies in a patient’s serum is the
a) Direct fluorescent-antibody test.
b) Indirect fluorescent-antibody test.
c) Southern Blotting
d) Northern Blotting
e) Polymerase Chain Reaction
b) Indirect fluorescent-antibody test.
A hybridoma results from the fusion of a(an)
a) Antigen with an antibody.
b) Antigen with a B cell.
c) Myeloma cell with a virus.
d) B cell with a myeloma cell.
e) B cell with a T cell.
d) B cell with a myeloma cell.
An antibiotic that attacks the LPS layer would be expected to have a narrow spectrum of activity. T/F?
True
Undergrowth of fungi after antibiotic use is commonly referred to as a superinfection. T/F?
False
Penicillin and streptomycin are commonly used in synergism because they display the same mode of action. T/F?
False
Antiviral drugs target viral processes that occur during viral infection. T/F?
True
Penicillin was considered a “miracle drug” for all of the following reasons EXCEPT
a) It has selective toxicity.
b) It kills bacteria.
c) It does not affect eukaryotic cells.
d) It inhibits gram-positive cell wall synthesis
e) It was the first antibiotic synthesized chemically.
e) It was the first antibiotic synthesized chemically.
Which of the following antibiotics is NOT bactericidal?
a) Penicillin
b) Cephalosporin’s
c) Rifampin’s
d) Polyenes
e) Aminoglycosides
d) Polyenes
The antibiotic cycloheximide binds to the 60S subunit
of the ribosome, as shown in Figure 1. The effect is to
a) Prevent peptide bond formation in
prokaryotes.
b) Prevent ribosome formation in bacteria.
c) Prevent mRNA-ribosome binding in
eukaryotes.
d) Prevent transcription in prokaryotes.
e) Prevent polypeptide elongation in
eukaryotes
E) prevent polypeptide elongation in eukaryotes
To date, most of our natural antibiotics have been found to be produced by members of what genus?
a) Cephalosporium
b) Streptomyces
c) Bacillus
d) Penicillium
e) Paenibacillus
b) Streptomyces
The antimicrobial drugs with the broadest spectrum of activity are
a) Chloramphenicol.
b) Penicillin G.
c) Aminoglycosides.
d) Tetra-cyclines.
e) Macrolides.
d) Tetra-cyclines.
Protozoan and helminthic diseases are difficult to treat because a) They do not reproduce. b) Their cells are structurally and functionally similar to human cells. c) They have more genes than bacteria. d) They replicate inside human cells. e) They do not have ribosomes.
b) Their cells are structurally and
functionally similar to human cells.
