Medical Microbiology 411 Quizzes 1 And 2

Front 1

Which of the following statements is/are true of the adaptive immune system in humans?

Select one:
A. it can recognize a very large number of molecules and structures
B. it can respond immediately the first time a pathogen is encountered
C. it can kill pathogen cells, but not host cells
D. both A and C
E. all of the above

Back 1

A. it can recognize a very large number of molecules and structures

Front 2

Which of the following statements is/are true of the innate immune system in humans?

Select one:
A. it can recognize a very large number of molecules and structures
B. it can respond immediately when a pathogen is encountered
C. it can kill pathogen cells, but not host cells
D. it has both humoral and cell-mediated components
E. both B and D

Back 2

E. both B and D

Front 3

Which of the following are cell-mediated effectors of the adaptive immune system?

Select one:
A. specific antibody
B. cytotoxic T-lymphocytes
C. macrophages
D. complement
E. natural killer cells

Back 3

B. cytotoxic T-lymphocytes

Front 4

Which of the following events occur during a local inflammatory response?

Select one:
A. extravasation of neutrophils
B. constriction of blood vessels
C. toxic shock
D. disseminated intravascular coagulation
E. both A and B

Back 4

A. extravasation of neutrophils

Front 5

Which of the following signs and symptoms of localized inflammation are caused by vasodilation?

Select one:
A. heat
B. pain
C. redness
D. swelling
E. both A and C

Back 5

E. both A and C

Front 6

Which of the following signs and symptoms of localized inflammation are caused by increased vascular permeability?

Select one:
A. heat
B. pain
C. redness
D. swelling
E. both B and D

Back 6

E. both B and D

Front 7

Which of the following cell types of the lymphoid lineage is phagocytic?

Select one:
A. plasma cells
B. natural killer cells
C. plasmacytoid dendritic cells
D. cytotoxic T lymphocytes
E. TH1 T-cells

Back 7

C. plasmacytoid dendritic cells

Front 8

Which of the following molecules can act as opsonins?

Select one:
A. complement factor small fragments
B. acute phase proteins
C. specific antibody
D. tumor necrosis factor α
E. both B and C

Back 8

E. both B and C

Front 9

Which of the following strategies is/are used by Coxiella burnetii, the causative agent of Q fever, to prevent it from being killed after uptake into host cells by phagocytosis?

Select one:
A. inhibits fusion between the phagosome and cytoplasmic granules (lysosomes)
B. resists toxic products and enzymes within the phagolysosome
C. secretes phospholipase to degrade the phagosome membrane before it can fuse with lysosomes
D. both A and B
E. all of the above

Back 9

B. resists toxic products and enzymes within the phagolysosome

Front 10

Which of the following are effector functions of complement small fragments?

Select one:
A. attract neutrophils
B. opsonize bacteria
C. form membrane attack complex (MAC)
D. activate natural killer cells
E. all of the above

Back 10

A. attract neutrophils

Front 11

Which of the following are beneficial effects of local, short-term inflammation?

Select one:
A. immune system effector molecules and cells are delivered to sites of infection
B. increased drainage of tissue fluid into lymph
C. generates physical barrier to spread of infection (clotting)
D. repair of injured tissue is promoted
E. all of the above

Back 11

E. all of the above

Front 12

Which of the following myeloid cell types are granulocytes?

Select one:
A. polymorphonuclear leukocytes
B. monocytes
C. dendritic cells
D. macrophages
E. both B and D

Back 12

A. polymorphonuclear leukocytes

Front 13

Which of the following humoral and/or cellular effectors of the innate immune system contribute most to the control of infections caused by viruses?

Select one:
A. complement
B. α/β-interferons
C. neutrophils
D. natural killer cells
E. both B and D

Back 13

E. both B and D

Front 14

Which of the following are effector functions of complement small fragments?

Select one:
A. attract neutrophils
B. opsonize bacteria
C. form membrane attack complex (MAC)
D. activate natural killer cells
E. all of the above

Back 14

E. all of the above

Front 15

α/β-interferons have which of the following functions?

Select one:
A. they activate endothelial cells and cause increased vascular permeability
B. they have antiviral effects
C. they act as chemoattractants for neutrophils
D. both A and C
E. all of the above

Back 15

B. they have antiviral effects

Front 16

Macrophages are a differentiated form of which of the following types of cells?

Select one:
A. neutrophils
B. myeloid dendritic cells
C. polymorphonuclear leukocytes
D. granulocytes
E. monocytes

Back 16

E. monocytes

Front 17

Which of the following archaea are opportunistic pathogens of humans?

Back 17

Archaea are NOT pathogenic to any host species.

Front 18

Which of the following act as barrier defenses against the entry of pathogens into the body?

Back 18

Skin, mucus, ciliated epithelial cells, and stomach acid are all examples of barrier defenses that act to prevent the entry of pathogens into the body.

1. Digestive Tract - Stomach acidity, Normal flora, Bile
2. Respiratory Tract - Mucus, Ciliated epithelium, Alveolar macrophages
3. Eyes - Tears, Lysozyme
4. Genitourinary Tract - Urination, Acidity of urine, Lysozyme, Vaginal lactic acid
5. Skin - Anatomic barrier, Antimicrobial secretions (glands)

Front 19

Cholera toxin is an example of a cytotonic enterotoxin. What is a cytotonic enterotoxin?

Back 19

A toxin that acts in the GI tract; does not cause the host cell to die; only changes are caused to the cell

entero = in GI tract
tonic = alters activity (vs -lytic which kills)

Front 20

Certain organisms, for example Salmonella Typhi, are able to establish a state of chronic carriage in some individuals. What does chronic carriage mean?

Back 20

Chronic carriage means that the host is PERMANENTLY colonized with a pathogen. Overt disease need not be caused.

Front 21

Which of the following is/are clinical signs of disease?

Back 21

Clinical signs - things that can be measured objectively/on the outside when someone has a disease (ie. FEVER, vital signs, breathing, respiration, HEART BEAT, PULSE, etc., BODY TEMPERATURE)

NOT pain or hunger (these are SYMPTOMS - things that effect a patient who has to report to a clinician)

Front 22

The Gram-positive bacterium, Clostridium difficile, an obligate anaerobe, can give rise to
endogenous infections that result in antibiotic-associated gastrointestinal disease. Which of the
following statements about C. difficile is/are correct?

Back 22

-presence will always cause disease
-grow best at low oxygen levels
-it's endogenous: meaning it is normally IN our intestines but doesn't cause disease until normal bacteria is wiped out by antibiotics

It can colonize the intestines of healthy people (it's there normally)

Front 23

What kind of relationship does a commensal microbe have with its host?

Back 23

Microbe benefits, but the host neither benefits or is harmed

Front 24

What happens when a pathogen infects a dead-end host?

Back 24

The pathogen cannot be transmitted to a new host

Front 25

Diphtheria toxin is an example of a cytolytic toxin. What is a cytolytic toxin?

Back 25

Cytolytic toxins result in direct death of host cell.

Front 26

What class of microbial pathogens causes most
endogenous infections of humans?

Back 26

- some opportunistic pathogens
- bacteria

Front 27

Which of the following is/are characteristics of organisms that establish exogenous infections in
humans?

Back 27

- They don't colonize humans before infecting them
- All are obligate pathogens
- Many opportunistic pathogens

Front 28

Which of the following are characteristics of a
facultative intracellular pathogen?

Back 28

- Facultative intracellular pathogens can reproduce/grow inside OR outside of the host cell.

-Always involves adhering to host cells - penetration not necessary

Front 29

Excessive cytokine production causes which of the following immunopathologies?

Back 29

- Toxic shock syndrome
- Delayed Type hypersensitivity (DTH) reactions
- chronic inflammation
- (all of the above)

Front 30

The Gram-negative bacterium, Campylobacter jejuni is generally considered to have a low
infective dose in humans. What does it mean to have a LOW infective dose?

Back 30

Only a FEW organisms are necessary to cause disease

Front 31

Which of the following mechanisms for local invasion of tissues potentially could be
employed by an obligate extracellular pathogen?

Back 31

- Hyaluronidase: degrades extracellular matrix and pathogens squeze down in between

- Exotoxin secretion: kills epithelial cells and makes a void to breach in

Front 32

Which of the following types of clinical specimens would not normally contain microorganisms
(i.e. the specimens come from normally sterile sites in the body)?

Back 32

Normally sterile sites:
1. Blood
2. Cerebrospinal fluid (CSF).
3. Pleural fluid (a.k.a. chest fluid, thoracentesis fluid).
4. Peritoneal fluid (a.k.a. abdominal fluid, ascites).
5. Pericardial fluid.
6. Bone (includes bone marrow).
7. Joint (e.g. synovial fluid; fluid, needle aspirate or
culture of any specific joint: knee, ankle, elbow, hip,
wrist).
8. internal body sites
(e.g. lymph node, brain, heart, liver, spleen, vitreous fluid, kidney, pancreas, or ovary)

Front 33

The Gram-positive, spore-forming bacterium Bacillus anthracis is an obligate pathogen of
humans. What is an obligate pathogen?

Back 33

A pathogen that ALWAYS causes disease when found a host.

Presence of organism = Disease

Front 34

In the context of medical microbiology, the term "Parasite" refers specifically to which of the
following?

Back 34

a non-fungal eukaryote that causes disease

Front 35

Which of the following may be consequences of a failure by the immune system to resolve an
infection?

Back 35

Death
Persistent Infection
Latent Infection
Reactivation

Front 36

Which of the following are routes by which pathogens potentially can disseminate within the
body?

Back 36

Blood
Lymph
Rarely - nerve cells

systemic spread of microbe after local invasion at or near PoE, loaclized infection or systemic disease

Front 37

When present in a bacterium, which of the following could be virulence factors?

Back 37

Mechanisms to breach/circumvent barriers to
invasion:
– enzymes to break down extracellular matrix
(ie. hyaluronidase).
– toxins to kill epithelial cells
– proteins to induce transcytosis

Mechanisms to survive in normally sterile sites (evade or counteract host immune responses):
- bacterial capsules
- ability to survive inside phagocytes

Front 38

Which of the following are virulence factors commonly found among protozoan parasites?

Back 38

???

Front 39

Among viruses that commonly cause human disease, which of the following result in active
replication and production of new virus particles?

Back 39

Infection without cell death

Lytic and non-lytic viruses

Front 40

Which of the following are possible outcomes of viral interaction with a cell?

Back 40

1. Abortive infection (Failed Infection)
2. Lytic Infection (Cell Death)
3. Persistent Infection (Replication without cell death)

Front 41

In which of the following situations would an opportunistic pathogen be likely to cause disease?

Back 41

1. Microbe has virulence factors
2. Large inoculum load
3. Access to normally sterile body sites
4. Weakened host immune system

Front 42

For Extracellular Bacterial Pathogens:

Extracellular bacterial pathogens can be detected in the body by _____________, or _____________, or _____________, of the INNATE IMMUNE SYSTEM.

After the pathogen has been detected, local inflammation will ensue. Innate immune system effectors _____________ and _____________ and _____________ will work to control the infection.

If the pathogen is not eliminated, an adaptive immune response is initiated.
_____________ migrate to the local draining lymph node, and activate _____________, which undergo clonal expansion and differentiate into _____________, or _____________. All the _____________ and a few of the _____________ activate _____________ which undergo clonal expansion and differentiate into _____________ that secrete _____________.

Adaptive immune system effectors, _____________ and _____________ are released into the blood circulation and move to sites of infection. _____________ binds to extracellular pathogen cells and _____________ them. _____________ binds to exotins and _____________ them. _____________ recognize macrophages via pathogen-specific antigen presented on _____________ and _____________ them.

Back 42

Extracellular bacterial pathogens can be detected in the body by MACROPHAGES, or DENDRITIC CELLS, or COMPLIMENT PROTEINS of the INNATE IMMUNE SYSTEM.

After the pathogen has been detected, local inflammation will ensue. Innate immune system effectors MACROPHAGES and NEUTROPHILS and COMPLIMENT will work to control the infection.

If the pathogen is not eliminated, an adaptive immune response is initiated.
DENDRITIC CELLS migrate to the local draining lymph node, and activate NAIVE CD4+ T CELLS which undergo clonal expansion and differentiate into TH1 CELLS or TH2 CELLS. All the TH2 CELLS and a few of the TH1 CELLS activate NAIVE B CELLS which undergo clonal expansion and differentiate into PLASMA CELLS that secrete ANTIBODY.

Adaptive immune system effectors, TH1 CELLS and ANTIBODY are released into the blood circulation and move to sites of infection. ANTIBODY binds to extracellular pathogen cells and OPSONIZES them. ANTIBODY binds to exotins and NEUTRALIZES them. TH1 CELLS recognize macrophages via pathogen-specific antigen presented on MHC II and ACTIVATE them.

Front 43

For Intracellular-cytoplasmic, VIRAL pathogens in typical host cells:

Intracellular viral pathogens can be detected in the body by M_________ and D_________ cells, or OTHER HOST CELLS.

After the pathogen has been detected, local inflammation ensues and _________ or _________ secreted from infected host cells, activate _________. The innate immune system effectors, _________ and _________, will work to control the infection.

If the pathogen is not eliminated, an adaptive immune response is initiated. _________ migrate to the local draining lymph node, and activate _________ cells and _________ cells which undergo clonal expansion and differentiate into _________ cells and _________. The _________ cells activate _________ which undergo clonal expansion and differentiate into _________ that secrete _________.

Adaptive immune system effectors, _________ and _________, are released into the blood circulation and move to sites of infection. _________ Binds to extracellular virus particles and _________ them. _________ recognize infected host cells via pathogen-specific antigen presented on _________ and _________ them.

Back 43

Intracellular viral pathogens can be detected in the body by MACROPHAGES and DENDRITIC cells, or OTHER HOST CELLS.

After the pathogen has been detected, local inflammation ensues and MACROPHAGES (via cytokines) or ANTI-VIRAL A/B INTERFERONS, secreted from infected host cells, activate NATURAL KILLER CELLS. The innate immune system effectors, NATURAL KILLER CELLS and A/B INTERFERONS, will work to control the infection.

If the pathogen is not eliminated, an adaptive immune response is initiated. DENDRITIC CELLS migrate to the local draining lymph node, and activate NAIVE CD4 T CELLS and NAIVE CD8 T CELLS which undergo clonal expansion and differentiate into TH2 cells and CYTOTOXIC T LYMPHOCYTES. The TH2 cells activate NAIVE B CELLS which undergo clonal expansion and differentiate into PLASMA CELLS that secrete ANTIBODY.

Adaptive immune system effectors, CYTOTOXIC T LYMPHOCYTES and ANTIBODY, are released into the blood circulation and move to sites of infection. ANTIBODY Binds to extracellular virus particles and NEUTRALIZES them. CYTOTOXIC T LYMPHOCYTES recognize infected host cells via pathogen-specific antigen presented on MHC 1 and KILL them.

Front 44

For Intracellular-cytoplasmic, NONVIRAL pathogens in all types of host cells:

Intracellular-cytoplasmic, non-viral pathogens can be detected in the body by _________ and _________.
After the pathogen has been detected, local inflammation ensues and M_________ activate N_________. Innate immune system effectors N_________ and NO HUMORAL EFFECTORS will work to control the infection.

If the pathogen is not eliminated, an adaptive immune response is initiated. _________ migrate to the local draining lymph node and activate _________ which undergo clonal expansion and differentiate into _________.

Adaptive immune system effectors, _________, are released into the blood circulation and move to sites of infection. _________ recognize infected host cells via pathogen-specific antigen presented on _________ and _________ them.

Back 44

Intracellular-cytoplasmic, non-viral pathogens can be detected in the body by MACROPHAGES and DENDRITIC CELLS.
After the pathogen has been detected, local inflammation ensues and MACROPHAGES activate NATURAL KILLER CELLS. Innate immune system effectors NATURAL KILLER CELLS and NO HUMORAL EFFECTORS will work to control the infection.

If the pathogen is not eliminated, an adaptive immune response is initiated. DENDRITIC CELLS migrate to the local draining lymph node and activate NAIVE CD8 T CELLS which undergo clonal expansion and differentiate into CYTOTOXIC T-LYMPHOCYTES.

Adaptive immune system effectors, CYTOTOXIC T LYMPHOCYTES, are released into the blood circulation and move to sites of infection. CYTOTOXIC T LYMPHOCYTES recognize infected host cells via pathogen-specific antigen presented on MHC 1 and KILL them.

Front 45

For Intracellular-vesicular (cellular) pathogens in macrophages:

Intracellular-vesicular bacterial pathogens can be detected in the body by infected _________.

After the pathogen has been detected, local inflammation will ensue. Among the innate immune system effectors NONE will be effect at controlling the infection

Because the pathogen is not eliminated, an adaptive immune response is initiated. _________ migrate to the local draining lymph node, and activate _________ which undergo clonal expansion and differentiate into _________.

Adaptive immune system effectors, _________ are released into the blood circulation and move to sites of infection. _________ recognize macrophages via pathogen-specific antigen presented on _________ and _________ them. The macrophages then are able to _________ the intracellular-vesicular pathogen inside them.

Back 45

Intracellular-vesicular bacterial pathogens can be detected in the body by infected MACROPHAGES.

After the pathogen has been detected, local inflammation will ensue. Among the innate immune system effectors NONE will be effect at controlling the infection

Because the pathogen is not eliminated, an adaptive immune response is initiated. DENDRITIC CELLS migrate to the local draining lymph node, and activate NAIVE CD4 T CELLS which undergo clonal expansion and differentiate into TH1 CELLS.

Adaptive immune system effectors, TH1 CELLS are released into the blood circulation and move to sites of infection. TH1 CELLS recognize macrophages via pathogen-specific antigen presented on MHC II and ACTIVATE them. The macrophages then are able to KILL the intracellular-vesicular pathogen inside them.