Infection Biology

Question 0

Cause disease only in immunocompromised people

Answer 0

Opportunistic pathogens

Question 1

Microbes that can cause disease

Answer 1

Pathogens

Question 2

Measure of a microbe’s ability to cause disease

Answer 2

Virulence

Question 3

Number of organisms required to cause disease in 50% of the population

Answer 3

ID50 Infective Dose 50

Question 4

Mediates attachment of bacteria

Answer 4

Pili

Question 5

Mediates strong adherence to the surface of human cells

Answer 5

Glycocalyx

Question 6

Surface proteins that mediate binding to endothelium and to extracellular proteins such as fibronectin

Answer 6

Curli

Question 7

Accelerates formation of a fibrin clot coating the organisms with a layer of fibrin

Answer 7

Coagulase

Question 8

Helps spread through subcutaneous tissue

Answer 8

Collagenase and Hyaluronidase

Question 9

Destroys both neutrophilic leukocytes and macrophages

Answer 9

Leukocidin

Question 10

Enumerate bacteria with IgA Protease

Answer 10

Streptococcus pneumoniae Haemophilus influenzae Neisseria Meningitidis Neisseria Gonorrhea SHiNe My Gong

Question 11

Protects against phagocytosis

Answer 11

Polysaccharide capsule

Question 12

Anticapsular antibodies allow more effective phagocytosis to occur

Answer 12

Opsonization

Question 13

Cell wall protein of S. pyogenes that is antiphagocytic

Answer 13

M protein

Question 14

Cell wall protein of S. aureus that prevents complement activation

Answer 14

Protein A

Question 15

Gram positive and negative bacteria Secreted from the cell Polypeptide Genes located in the plasmid or bacteriophage High toxicity High antigenicity Can be used as vaccines Destroyed rapidly at 60C

Answer 15

Exotoxins

Question 16

Gram negative bacteria Not secreted from the cell Lipopolysaccharide Genes are found in the bacterial chromosome Low toxicity Low antigenicity No vaccine available Stable at 100C for an hour

Answer 16

Endotoxins

Question 17

What kind of toxins does tetanus and botulism exhibit A) Endotoxin B) Exotoxin

Answer 17

B) Exotoxin

Question 18

What kind of toxins does meningococcemia exhibit A) Endotoxin B) Exotoxin

Answer 18

A) Endotoxin

Question 19

Polypeptides secreted by certain bacteria that alter specific cell functions resulting in the symptoms of disease

Answer 19

Exotoxin

Question 20

The ONLY exotoxin secreting bacteria that is heat-labile

Answer 20

Staphylococcal enterotoxin

Question 21

Inhibits elongation of factor II Basically, inhibits protein synthesis

Answer 21

ADP ribosylation

Question 22

Located in the outer membrane of gram negative bacteria

Answer 22

Lipopolysaccharides

Question 23

The toxic component of lipopolysaccharides

Answer 23

Lipid A

Question 24

1) induces the overproduction of cytokines like TNF and IL1 2) activates the complement cascade 3) activates the coagulation cascade resulting in DIC

Answer 24

Lipid A

Question 25

All bacteria have cell walls composed of peptidoglycan EXCEPT

Answer 25

Mycoplasma pneumoniae (Sterol instead of peptidoglycan)

Question 26

All gram-positive bacteria have NO endotoxin EXCEPT

Answer 26

Listeria monocytogenes

Question 27

All bacterial capsules are composed of polysaccharide EXCEPT

Answer 27

Bacillus anthracis

Question 28

Gram positive cocci Determines pattern of hemolysis

Answer 28

Blood agar

Question 29

Enteric gram negative rods Selects against gram positive bacteria Differentiates between lactose fermenters and nonfermenters

Answer 29

MacConkey Eosin-methylene blue

Question 30

Distinguishes lactose fermenters from nonfermenters Distinguishes H2S producers from nonproducers

Answer 30

Triple sugar iron (TSI)

Question 31

Agar used for Clostridium perfringens

Answer 31

Egg yolk

Question 32

Agar used for Corynebacterium diphtheriae

Answer 32

Tellurite

Question 33

Agar used for group D streptococci

Answer 33

Bile esculin

Question 34

Agar used for staphylococci

Answer 34

Mannitol salts

Question 35

Agar used for N. meningitidis, N. gonorrhoeae from STERILE sites

Answer 35

Chocolate

Question 36

Agar used for N. gonorrhoeae from NONSTERILE sites

Answer 36

Thayer-Martin

Question 37

Agar used for Haemophilus influenzae

Answer 37

Chocolate + Factors X and V

Question 38

Agar used for Mycobacterium tuberculosis

Answer 38

Löwenstein-Jensen

Question 39

Agar used for Vibrio Cholerae

Answer 39

Thiosulfate Citrate Bile Salts (TCBS)

Question 40

Agar used for Bordetella pertussis

Answer 40

Bordet-Gengou

Question 41

Agar used for Legionella pneumophila?

Answer 41

Charcoal-yeast extract

Question 42

Agar used for Campylobacter or Helicobacter?

Answer 42

Skirrows (Campi's)

Question 43

Agar used for Borrelia burgdorferi?

Answer 43

Barbour-Stoenner-Kelly (BSK)

Question 44

Agar used for Mycoplasma pneumoniae?

Answer 44

Eaton

Question 45

Agar used for Pseudomonas aeruginosa?

Answer 45

Cetrimide

Question 46

Agar used for Salmonella and Shigella?

Answer 46

Xylose-Lysine-Deoxycholate (XLD)

Question 47

Agar used for Leptospira interrogans?

Answer 47

Ellinghausen-McCullough-Johnson-Harris (EMJH) / Fletcher's

Question 48

Determines whether antibodies are present in the patient's serum Detects the antigens of the organism in tissues or body fluids At least a fourfold increase in titer between the acute and convalescent samples

Answer 48

Serologic tests

Question 49

Test that is highly specific, quite sensitive and much faster than culture Especially useful for those bacteria that are difficult to culture What is this test and give examples of the organisms?

Answer 49

Molecular tests (Nucleic acid amplification tests, nucleic acid probes, and nucleic acid sequence analysis) Chlamydia and Mycobacterium