Microbial Mechanisms

Question 1

capability of pathogen to cause disease

Answer 1

virulence

Question 2

portals of entry

Answer 2

mucous membrane, skin, parenteral routes

Question 3

number of invading microbes of virulence

Answer 3

ID50

Question 4

number of invading microbes of toxin potency

Answer 4

LD50

Question 5

infectious dose - bacillus anthracis

Cutaneous anthrax = ___ to ____ endospores

Answer 5

10 to 50

Question 6

infectious dose - bacillus anthracis

Inhalation anthrax = ___ to ____ endospores

Answer 6

10,000 to 20,000

Question 7

infectious dose - bacillus anthracis

Gastrointestinal anthrax = ___ to ____ endospores

Answer 7

250,000 to1,000,000 endospores

Question 8

lethal dose

botulinum toxin in mice = ______ ng/kg

Answer 8

0.03

Question 9

lethal dose

shiga toxin = ______ ng/kg

Answer 9

25

Question 10

DIVERSITY OF ADHESINS

attaches to teeth by means of its glycocalyx which is primarily made up of DEXTRAN

Answer 10

streptococcus mutans

Question 11

DIVERSITY OF ADHESINS

have fimbriae that adhere to the glycocalyx of S. mutans

Answer 11

actinomyces

Question 12

DIVERSITY OF ADHESINS

have adhesions on fimbriae that adhere ONLY to SPECIFIC kinds of cells in the small intestine

Answer 12

shigella and e. coli

Question 13

DIVERSITY OF ADHESINS

uses tapered end as a hook to attach to host cells

Answer 13

treponema pallidum

Question 14

DIVERSITY OF ADHESINS

produces an adhesion for a specific receptor on a host cell

Answer 14

listeria monocytogenes

Question 15

DIVERSITY OF ADHESINS

has a fimbriae with adhesions

Answer 15

neisseria gonorrhoeae

Question 16

DIVERSITY OF ADHESINS

has a mechanism of adherence that resembles viral attachment

Answer 16

staphylococcus auerus

Question 17

enzyme that coagulate blood (e.g. Staphylococci)

Answer 17

coagulase

Question 18

enzyme that digest fibrin clots (e.g. S. pyogenes)

Answer 18

kinases (fribrinolysin)

Question 19

enzyme that hydorlyzes hyaluronic acid (e.g. Streptococci)

Answer 19

hyaluronidase

Question 20

enzyme that hydrolyzes collagen (e.g. Clostridium)

Answer 20

collagenase

Question 21

enzyme that destroy IgA antibodies (e.g. N. gonorrhoeae and N. meningitidis)

Answer 21

IgA proteases

Question 22

enzyme that break down RBC (e.g. Staphylococci)

Answer 22

hemolysins

Question 23

enzyme that breaks fown phospholipids, destroy plasma membrane of RBC (e.g. C. perfringens)

Answer 23

lecithinase

Question 24

enzyme that destroy neutrophils (e.g. Staphylococci & Streptococci)

Answer 24

leukocidins - toxin

Question 25

process of altering surface antigens thus evading immune response

Answer 25

antigenic variation

Question 26

surface proteins that rearrange nearby actin filaments of the cytoskeleton

Answer 26

invasins

Question 27

a glycoportein that bridges the junctions between cells; used by certain microbes to move from cell to cell

Answer 27

cadherin

Question 28

proteins that exhibit a high affinity to iron (e.g. Enterobacatin [E. Coli], Bacillibactin [B. subtilis, B. anthracis], Vibriobactin [V. cholerae]

Answer 28

siderophores

Question 29

poisonous substances that are produced by certain microorganisms

Answer 29

toxins

Question 30

capacity of microorganisms to produce toxins

Answer 30

toxigenicity

Question 31

referes to the presence of toxin in blood

Answer 31

toxemia

Question 32

TYPE OF TOXIN produced mostly by gram + bacterium; chiefly made up of protein; part of growth and metabolism; released following LYSIS of bacterial cell; carried by BACTERIAL PLASMIDS; soluble in fluids; most LETHAT substances known; disease specific

Answer 32

exotoxins

Question 33

antibodies produced by the body provides immunity to exotoxins

Answer 33

antitoxins

Question 34

inactivated toxin used in a vaccine

Answer 34

toxoids

Question 35

3 principal types of exotoxin

Answer 35

A-B Toxins, Membrane-disrupting toxins, superantigens

Question 36

also called as TYPE III TOXINS; 1st toxins to be studied; 2 parts designated A & B (both polypeptides); common example is Diphtheria toxin

Answer 36

A-B Toxins

Question 37

what part of A-B toxins is the active (enzyme) component

Answer 37

A

Question 38

part of A-B toxins that is the binding component

Answer 38

B

Question 39

also called TYPE II TOXINS

Answer 39

Membrane-disrupting toxins

Question 40

membrane-disrupting toxins that kill phagocytic leukocytes

Answer 40

leukocidins (staphylococci, streptococci & pneumococci)

Question 41

membrane-disrupting toxins that destroy ERYTHROCYTES

Answer 41

hemolysin (streptococci)

Question 42

also called TYPE I TOXINS; bacterial proteins

Answer 42

superantigens

Question 43

they stimulate the proliferation of immune cells called T cells with release of enormous amounts of cytokines

Answer 43

superantigens

Question 44

they include the staphylococcal toxins that cause food poisoning and toxic shock syndrome

Answer 44

superantigens

Question 45

TYPE OF TOXIN chiefly made up of LPS (lipopolysaccharides); released when bacteria dies, and cell walls lyse; stimulates macrophage to release cytokines in very high concentrations

Answer 45

endotoxins

Question 46

toxins that produce the same signs and symptoms (chills, fever, weakness, generalized aches in some cases, shock, and death); can induce MISCARRIAGE

Answer 46

endotoxins

Question 47

toxins that have severe consequences including: DIC and Shock; microbes that produce such: S. typhi, Proteus, N. meningitidis

Answer 47

endotoxins

Question 48

small, circular, DNA molecules capable of independent replication; resistance (R) factors

Answer 48

plasmids

Question 49

incorporation of VIRAL DNA into the bacterial chromosome; newly integrated genetic material is now called a PROPHAGE

Answer 49

lysogeny

Question 50

a bacterial cell containing a prophage

Answer 50

lysogenic

Question 51

exhibition of new properties coded by the prophage in the bacterial cell, both the host cell and its progeny

Answer 51

lysogenic conversion

Question 52

stops mitosis; releaase enzymes of host cell; formation of inclusion bodiesl fusion of adjacent infected cells (syncytium or giant cells)

Answer 52

cytopathic effects of viruses

Question 53

changes in host cell's function w/o visible changes; some virus-infected cells produce substances called INTERFERONS

Answer 53

cytopathic effects of viruses

Question 54

induction of antigenic changes in the surface of the infected cells; induction of chromosomal changes in host cell; loss of contact inhibition

Answer 54

cytopathic effects of viruses

Question 55

doesn't have a well-defined set of virulence factors

Answer 55

fungi

Question 56

they inhibit CHON synthesis; causes headaches, chills, severe nausea, vomiting, and visual disturbances; produced by FUSARIUM (grains and rice)

Answer 56

trichothecenes (toxin)

Question 57

produces capsules

Answer 57

cyrptococcus neoformans

Question 58

an alkaloid; produced by CLAVICEPS PURPUREA; found in SCLEROTIA; causes hallucinations and limb gangrene

Answer 58

toxin ergot

Question 59

produced by aspergillus flavus; found in NUTS which is CARCINOGENIC

Answer 59

aflatoxin

Question 60

examples: phalloidin and amanitin; produced by AMANITA PHALLOIDES (death angel); amanita mushrooms MAY RESULT IN DEATH

Answer 60

mycotoxins

Question 61

invade host cells and reproduce within them, causing their rupture

Answer 61

plasmodium

Question 62

attaches to macrophages and gains entry by phagocytosis

Answer 62

toxoplasma

Question 63

attach to host cells and digest the cells and tissue fluids

Answer 63

giardia lamblia

Question 64

produces neurotoxins; example: SAXITOXIN (produced by some genera of DINOFLAGELLATES such as Alexandium; causes PARALYTIC SHELLFISH POISONING)

Answer 64

algae

Question 65

use host tissues for growth and metabolism; waste products can lead to disease symptoms

Answer 65

helminths