Infection Biology

Question 0

Can cause disease only in immunocompromised people

Answer 0

Opportunistic pathogens

Question 1

Microbes that can cause disease

Answer 1

Pathogens

Question 2

Measure of microbe’s ability to cause virulence

Answer 2

Virulence

Question 3

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

Answer 3

ID50

Question 4

Mechanisms of bacterial disease

Answer 4

1. Production of toxins

2. Induction of inflammation

Question 5

Refers to inanimate object that can harbor pathogens

Answer 5

Fomites

Question 6

Surface proteins of Salmonella and E.coli that mediate binding to endothelium and to extracellular proteins such as fibronectin

Answer 6

Curli

Question 7

Enzymes in bacterial invasion that spread through subcutaneous tissue

Answer 7

Collagenase and hyaluronidase

Hyaluronidase - is a spreading factor

Question 8

Bacterial enzyme that accelerates formation of a fibrin clot coating the organisms with a layer of fibrin

Answer 8

Coagulase

Question 9

Bacterial enzyme that allows adherence to mucous membranes

Answer 9

IgA protease

Question 10

Bacterial enzyme that destroys both neutrophilic leukocytes and macrophages

Answer 10

Leukocidin - leukocidal

Question 11

Bacteria with IgA protease

Answer 11

Streptococcus pneumoniae
Haemophilus influenzae
N.meningitides
N.gonorrhoeae

Question 12

Toxin with low toxicity, low antigenicity with no available vaccine

Answer 12

Endotoxin

Question 13

Toxins that are destroyed rapidly at 60oC except Staphylococcal enterotoxin

Answer 13

Exotoxin

Question 14

The active subunit of exotoxin, less toxic in toxoids

Answer 14

A subunit

Question 15

Binding subunit of exotoxin

Answer 15

B subunit

Question 16

Can elicit widespread activation of the complement and coagulation cascades. Highly toxic at small amount

Answer 16

Superantigens

Question 17

Toxic component of LPS

Answer 17

Lipid A

Question 18

All bacteria have cell walls composed of peptidoglycan except

Answer 18

Mycoplasma pneumoniae

Question 19

All gram positive bacteria have no endotoxin except

Answer 19

Listeria monocytogenes

Question 20

All bacteria capsules are composed of polysaccharide except

Answer 20

Bacillus anthracis

Question 21

All exotoxins are heat-labile except

Answer 21

Staphylococcal enterotoxin - heat stable

Question 22

Gold standard for bacteriologic test

Answer 22

Culture

Question 23

Media that determines the pattern of hemolysis

Answer 23

Blood agar - isolate various gram positive cocci, selective

Question 24

Media that differentiates lactose fermenters and nonfermenters, selects against gram negative bacteria

Answer 24

MacConkey - enteric gram negative rods | Eosin-methylene blue (EMB) - enteric gram negative rods

Question 25

Media for distinguishing H2S producers from non-producers

Answer 25

Triple sugar Iron (TSI)

Question 26

Uses egg yolk agar, it destroys lecithin

Answer 26

Clostridium perfringens

Question 27

Corynebacterium diphtheriae uses what type of agar?

Answer 27

Tellurite

Question 28

Group D streptococci uses what agar?

Answer 28

Bile Esculin

Question 29

Chocolate agar for what?

Answer 29

N.meningitidis | N.gonorrhoeae from sterile sites

Question 30

N.gonorhoeae from non-sterile sites uses what agar?

Answer 30

Thayer-Martin medium

Question 31

Thayer-Martin medium uses three | antibiotics?

Answer 31

Vancomycin, Colestin and Nystatin

Question 32

Haemophilus influenzae uses what agar?

Answer 32

Chocolate+factors X and V

Question 33

Agar for Mycobacterium tuberculosis

Answer 33

Lowenstein -Jensen agar

Question 34

Vibrio cholerae agar

Answer 34

Thiosulfate citrate bile salts sucrose agar (TCBS)

Question 35

Bordet-Gengou / Regan-Lowe agar

Answer 35

Bordetella pertussis

Question 36

Charcoal-yeast extract agar

Answer 36

Legionella pneumophila

Question 37

Agar for Campylobacter and Helicobacter

Answer 37

Skirrows/Campy's agar

Question 38

Agar for Borrelia burgdorferi

Answer 38

Barbour-Stoenner-Kelly (BSK) agar

Question 39

Eaton agar

Answer 39

Mycoplasma pneumoniae

Question 40

Uses Cetrimide agar

Answer 40

Pseudomonas aeruginosa

Question 41

Agar for Salmonella and Shigella

Answer 41

Xylose-Lysine-Deoxycholate (XLD)

Question 42

Agar for Leptospira interrogans

Answer 42

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