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

Virulence factors

Answer 3

Capsules
Exotoxins
Endotoxins

Question 4

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

Answer 4

ID50

Question 5

Presence of microbes in the body and symptoms of disease

Answer 5

Infection

Question 6

Mechanisms of bacterial disease

Answer 6

Production of toxins

Induction of inflammation

Question 7

Modes of Transmission: Human to Human

Answer 7

Direct: sexual or transvaginal
Fecal-oral
Inhalation
Transplacental
Blood-borne

Question 8

Modes of Transmission: Nonhuman to Human

Answer 8

Soil
Water
Direct animal source
Vector-borne
Animal excreta
Fomites

Question 9

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

Answer 9

Curli

Question 10

Spread through subcutaneous tissue

Answer 10

Hyaluronidase (destroy connective tissue)

Collagenase

Question 11

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

Answer 11

Coagulase

Question 12

Allows adherence to mucous membranes

Answer 12

Immunoglobulin A (IgA) protease

Question 13

Destroys both neutrophilic leukocytes and macrophages

Answer 13

Leukocidin

Question 14

Leukocidin of Staphylococcus aureus

Answer 14

Panton Valentine Leukocidin (PV Leukocidin)

Question 15

Bacteria with IgA protease

Answer 15

Streptococcus pneumonia
Haemophilus influenzae
Neisseria meningitidis
Neisseria gonorrhoeae

Question 16

Protect against phagocytosis; Antiphagocytic factor

Answer 16

Polysaccharide Capsule

Question 17

Proteins produced to attach to bacteria to be easily engulfed

Answer 17

Opsonins

Question 18

Anticapsular antibodies allow more effective phagocytosis to occur

Answer 18

Opsonization

Question 19

Cell protein of S. pyogenes: antiphagocytic

Answer 19

M protein

Question 20

Cell wall protein of S. aureus that prevents complement activation

Answer 20

Protein A

Question 21

Source of Exotoxin

Answer 21

Gram (+) and (-)

Question 22

Source of Endotoxin

Answer 22

Gram (-)

Question 23

Secreted from cell: Endotoxin or Exotoxin?

Answer 23

Exotoxin

Question 24

Chemistry of Exotoxin

Answer 24

Polypeptide

Question 25

Chemistry of Endotoxin

Answer 25

Lipopolysaccharide

Question 26

Location of genes: Exotoxin

Answer 26

Plasmid or Bacteriophage

Question 27

Location of genes: Endotoxin

Answer 27

Bacterial chromosome

Question 28

Toxicity of Exotoxin

Answer 28

High

Question 29

Toxicity of Endotoxin

Answer 29

Low

Question 30

Antigenicity of Exotoxin

Answer 30

High

Question 31

Antigenicity of Endotoxin

Answer 31

Low

Question 32

Used for vaccines

Answer 32

Exotoxins (Endotoxin: No available vaccine)

Question 33

Heat stability of Exotoxins

Answer 33

Destroyed rapidly at 60C (Except Staphylococcal enterotoxin - heat stable)

Question 34

Heat stability of Endotoxins

Answer 34

Stable at 100C for 1 hour

Question 35

Overreactive immune response; Can elicit widespread activation of the complement and coagulation cascades

Answer 35

Superantigen

Question 36

Toxin diluted with formalin

Answer 36

Toxoid

Question 37

Active subunit of Exotoxin

Answer 37

A subunit

Question 38

Binding subunit of Exotoxin

Answer 38

B subunit

Question 39

Exotoxin of Diphtheria toxin, Cholera toxin, Escherichia coli heat-labile toxin, Pertussis toxin

Answer 39

ADP-ribosylation (leads to Protein synthesis inhibition)

Question 40

Exotoxin of Toxic Shock Syndrome toxin, Staphylococcal enterotoxin, Erythrogenic toxin

Answer 40

Superantigen (highly toxic; cause hyperimmune reaction)

Question 41

Exotoxin of Tetanus toxin, Botulinum toxin, Lethal factor of anthrax toxin, Scalded skin toxin

Answer 41

Protease

Question 42

Exotoxin of Clostridium perfringens alpha toxin

Answer 42

Lecithinase

Question 43

The toxic component of LPS; Overproduction of cytokines; Activates complement cascade; Activates coagulation cascade

Answer 43

Lipid A

Question 44

All bacteria have cell walls composed of peptidoglycan EXCEPT

Answer 44

Mycoplasma pneumoniae

Question 45

All gram (+) bacteria have NO endotoxin EXCEPT

Answer 45

Listeria monocytogenes

Question 46

All bacteria capsules are composed of polysaccharide EXCEPT

Answer 46

Bacillus anthracis

Question 47

All exotoxins are heat-labile EXCEPT

Answer 47

Staphylococcal enterotoxin

Question 48

Bacteria isolated: Various gram (+) cocci; Determines pattern of hemolysis

Answer 48

Blood Agar

Question 49

Bacteria isolated: Various gram (-) rods; Selects against gram (+) bacteria and differentiates between lactose fermenters and nonfermenters

Answer 49

MacConkey Agar | Eosin-methylene blue (EMB) Agar (selective)

Question 50

Bacteria isolated: Various gram (-) rods; Distinguishes lactose fermenters from nonfermenters and H2S producers from nonproducers

Answer 50

Triple sugar iron (TSI)

Question 51

Agar: Clostridium perfringers

Answer 51

Egg-yolk Agar

Question 52

Agar: Corynebacterium diphtheriae

Answer 52

Tellurite Agar

Question 53

Agar: Group D Streptococci

Answer 53

Bile Esculin Agar

Question 54

Agar: Staphylococci

Answer 54

Mannitol salts Agar

Question 55

Agar: N. Meningitidis; N. gonorrhoeae from sterile sites

Answer 55

Chocolate Agar

Question 56

Agar: N. gonorrhoeae from nonsterile sites

Answer 56

Thayer-martin Agar

Question 57

Agar: Haemophilus influenzae

Answer 57

Chocolate + Factor X and V Agar

Question 58

Antibiotics added in Thayer-Martin Medium

Answer 58

Vancomycin (gram +) Celestine (gram -) Nystatin (fungi)

Question 59

Medium: Grows 1 group, Will not allow other group to grow

Answer 59

Selective Medium

Question 60

Medium: Differentiate biochemical characteristics

Answer 60

Differential Medium

Question 61

Agar: Mycobacterium tuberculosis

Answer 61

Lowenstein-Jensen Medium

Question 62

Agar: Vibrio cholerae

Answer 62

Thiosulfate Citrate Bile Salts Medium

Question 63

Agar: Bordetella pertussis

Answer 63

Bordet-Gengou or Regan-Lowe Medium

Question 64

Agar: Legionella pneumophila

Answer 64

Charcoal-yeast extract Medium

Question 65

Agar: Campylobacter, Helicobacter

Answer 65

Skirrow's or Campy's Medium

Question 66

Agar: Borrelia burgdorferi

Answer 66

Barbour-Stoenner-Kelly (BSK) Medium

Question 67

Agar: Mycoplasma pneumoniae

Answer 67

Eaton Medium

Question 68

Agar: Pseudomonas aeruginosa

Answer 68

Cetrimide Medium

Question 69

Agar: Salmonella, Shigella

Answer 69

Xylose-Lysine-Deoxycholate (XLD) Medium

Question 70

Agar: Leptospira interrogans

Answer 70

Ellinghausen-McCullough-Johnson-Harris (EMJH) Medium

Question 71

Mycobacterium leprae

Answer 71

No culture medium (in vivo growth)