exam 3 Flashcards
Biochemical tests include all of the following except_________.
A) presence of catalase
B) presence of oxidase
C) colony morphology
D) sugar fermentation
E) gas production
Colony morphology
Which sample does not require sterile needle aspiration?
A. Feces
B. CSF (cerebrospinalfluid)
C. Blood
Feces
What type of test will detect minute amount of soluble antigens?
A. Precipitation
B. Agglutination
C. Specificity
D. sensitivity
Precipitation
Which of the following is not one of the main categories for identifying microbes?
A) Radiologic
B) Phenotypic
C) Genotypic
D) Immunologic
Radiologic
Which medium contains three sugar sources and allows to differentiate between Salmonella, Shigella, Ecoli and Pseudomonas?
A) Triple sugar Iron Agar
B) EMB
C) McConkey
D) MTM
Triple sugar iron agar
What is the purpose of selective media?
a) To inhibit the growth of specific organisms
b) To differentiate between bacteria based on growth and appearance
c) To enhance the growth of fastidious organisms
d) To identify antibiotic resistance
To inhibit the growth of specific organisms
What diagnostic technique is mismatched?
A) EIA(enzymelinkedimmunoassay)-detectingantibodies(orantigen)usingenzymatic
reaction as a reporter
B) IF(Immunofluorescence)-detectingantibodies(orantibodies)usingfluorescentdyeas
a reporter
C) PCR (polymerase chain reaction - Detecting specific pathogen DNA using nucleic acid
probes
D) Microscopy - observation of stained cells or colonies on the plate
PCR (polymerase chain reaction - Detecting specific pathogen DNA using nucleic acid
probes
Phenotypic methods of identifying microorganisms in a patient sample are characterized as those that_________.
A) directly examine the organism’s appearance or behavior, which includes its metabolic abilities, environmental preferences and drug susceptibilities
B) analyze the genetic makeup of the microorganism, which conclusively diagnoses the infection
C) make use of the patient’s antibodies to precipitate the microorganism out of solution, or agglutinate the antigens in the sample
D) make use of color-changing antibodies directed against the microbe that will become visible to the naked eye when bound
Directly examine the organism’s appearance or behavior, which includes its metabolic abilities, environmental preferences, and drug susceptibilities
What is the primary difference between general-purpose media and selective media? a) Selective media are used to differentiate between different bacterial types. b) General-purpose media promote the growth of all microorganisms. c) Selective media inhibit the growth of certain bacteria. d) General-purpose media are only used for fungal cultures.
General-purpose media promote the growth of all microorganisms.
Which type of media is most appropriate for culturing Escherichia coli from a urinary tract infection? a) Blood agar b) MacConkey agar c) Triple-sugar iron (TSI) agar d) Thayer-Martin agar
MacConkey agar
How does the use of differential media help in the identification of bacteria? a) It provides a nutrient source for all bacteria. b) It allows for the visualization of different metabolic reactions. c) It prevents the growth of harmful bacteria. d) It inhibits the growth of anaerobic bacteria.
It allows for the visualization of different metabolic reactions.
What challenge is associated with the isolation of anaerobic pathogens? a) They are difficult to culture in the presence of oxygen. b) They grow rapidly on selective media. c) They do not survive well in the human body. d) They are resistant to most antibiotics.
They are difficult to culture in the presence of oxygen.
What is the purpose of a serial dilution tube test in antimicrobial susceptibility testing? a) To determine the smallest amount of agent needed to inhibit microbial growth. b) To distinguish
between aerobic and anaerobic bacteria. c) To differentiate between pathogenic and non-pathogenic bacteria. d) To identify the source of a urinary tract infection.
To determine the smallest amount of agent needed to inhibit microbial growth.
Adaptive immunity involves the response of_________.
A) skin barriers
B) B and T lymphocytes
C) lysozyme
D) mucous membranes
E) interferon
B and T lymphocytes
What type of cells secretes cytokines and helps to activate other immune cells? A) T cells
B) B cells
C) Dendritic cells D) Mast cells
T cells
- Killed or inactivated vaccines are prepared by_________.
removal of virulence genes from the microbe
treatment with formalin, heat, or radiation
passage of the pathogen through unnatural hosts or tissue culture long-term subculturing of the microbe
Allofthechoicesarecorrect
Treatment with formalin, heat, or radiation
Which of the following contribute to the limitless diversity generated from a relatively fixed number of immunoglobulin genes?
A)Random heavy and light chain reassortment only
B)Hypermutation, random heavy and light chain reassortment, and somatic recombination C)Hypermutation only
D)Somatic recombination only
Hypermutation, random heavy and light chain reassortment, and somatic recombination
The selection of T cells in thymus results in formation of
A) T-cells that are able to recognize self but do not bind too hard to it
B) T cells that are able to recognize self and bind hard to it
C) T cells that are unable to recognize self and only bind foreign antibodies
D) T cells that are unable to recognize self and unable to bind foreign antibodies
T-cells that are able to recognize self but do not bind too hard to it
What type of immunity is associated with B cells? A. Intracellular immunity
B. Humoral immunity
C. Tolerance immunity
D. Adaptive immunity
Humoral immunity
What is the exact purpose of T cell positive selection in the thymus?
A. To eliminate T cells that bind strongly to self-antigens
B. To retain T cells that can recognize MHC and self-peptides, but don’t bind too strongly to them
C. To generate memory T cells
D. To eliminate T cells that can not recognize MHC and self peptides
To retain T cells that can recognize MHC and self-peptides, but don’t bind too strongly to them
Which of the following is an intrinsic factor that determines immunogenicity? A. Size and nature of the molecule
B. Route of antigen exposure
C. Antigen dose
D. Presence of antibodies
Size and nature of the molecule
What is the role of MHC molecules in antigen recognition by T cells? A. To produce antibodies that bind to antigens
B. To present antigens to T cell receptors
C. To enhance antibody-antigen interaction
D. To eliminate antigens through phagocytosis
To present antigens to T cell receptors
What does the process of clonal selection in B cells involve? A. B cells binding to MHC molecules
B. Production of multiple types of antibodies by a single B cell C. Proliferation of antigen-specific B cells after activation
D. Elimination of B cells that bind weakly to antigens
Proliferation of antigen-specific B cells after activation
Which of the following is a key characteristic of active immunity?
A) Immunity is conferred immediately
B) No exposure to antigen is required
C) It develops memory cells, leading to long-lasting immunity
D) It involves the transfer of pre-formed antibodies
It develops memory cells, leading to long-lasting immunity