Chapter 15: Mechanisms of Pathogencitiy

Question 1

What are 3 examples of portal of entry

Answer 1

• mucous membrane
• skin
• parental route

Question 2

Examples of the parental route

Answer 2

• infection sites
• wounds
• insect bites

Question 3

what kind of organism can enter through the skin

Answer 3

staphylococcus

Question 4

where are mucous membranes in the human body

Answer 4

• respiratory tract (TB)
• GI tract
• GU tract (STD)
• conjunctiva (measles)

Question 5

what is the easiest poratl of entry

Answer 5

respitory tact

Question 6

exoenzymes produce

Answer 6

toxins

Question 7

toxin definition

Answer 7

substances that contribute to pathogenicity

Question 8

Toxigenicity definition

Answer 8

ability to produce a toxin

Question 9

Toxemia definition

Answer 9

presence of toxin in the hosts blood

Question 10

toxoid defintion

Answer 10

inactivated taxin used in a vaccine

Question 11

antitoxin defintion

Answer 11

antibodies against a specific toxin

Question 12

characteristics od exoenzymes

Answer 12

• coagulase
• kinase
• hyaluronidase
• collagenase

Question 13

coagulase

Answer 13

coagulates blood
fibrogen –> fibrin

Question 14

example of organisms who use coagulase

Answer 14

s. aureus

Question 15

kinase purpose

Answer 15

dissolves clots

Question 16

examples of organism who use kinase

Answer 16

s. pyogenes

Question 17

collagenase purpose

Answer 17

breaks down collagen

Question 18

examples of organsims who use collagenase

Answer 18

c. perfriges (GANGREEN)

Question 19

what does hyaluronidase do

Answer 19

blackens skin

Question 20

examples of organsims who use hyaluronidase

Answer 20

• closterdium perfringes (gangreen)
• s. pyogenes

Question 21

what are the two types of toxins

Answer 21

• exotoxin
• endotoxin

Question 22

exotoxin is produced by

Answer 22

mostly gram positive bacteria
- produced as a part of growth

Question 23

endotoxin is produced by

Answer 23

gram negative bacteria
- lipid A

Question 24

exotoxins produce ______ sings / symptoms

Answer 24

specific

Question 25

endotoxins produce ______ signs / symptoms

Answer 25

general

Question 26

exotoxins are ______ in nature

Answer 26

protein

Question 27

exotoxins are neutralized by

Answer 27

Ig antibodies (antitoxins)

Question 28

example of a toxiod

Answer 28

DTap vaccine

Question 29

what are general symptoms

Answer 29

- fever - GI tract: nausea, vomiting, diaheaa / dysentery - shock

Question 30

are antibodies produced in responce to endotoxins

Answer 30

no

Question 31

shock pathway

Answer 31

phagocytosis --> triggers Tumor Necrosis Factor or Cachetin --> released to the blood --> vital organs --> impense drops in blood pressure --> organs shut down

Question 32

fever pathway

Answer 32

phagocytosis --> destroy and digest --> lysosomes release enzymes --> release IPS --> release cytokines --> interlukin (IL-1), called: endogenous pyrogens --> circulates --> reaches hypothalamus --> prostaglandin released --> resets temp --> fever - chills ( increased IL-1, shivers) OR - Crisis (decreased IL-1, sweating)

Question 33

what are the three classes of exotoxins

Answer 33

- classic AB - membrane disrupting - Superantigens

Question 34

what are the four examples of classic A+B

Answer 34

- C. diphteriae - Botulinum toxin - tetanopasmin - vibriotoxin

Question 35

C. dipteriae

Answer 35

B =binds A = shuts down protein synthesis --> causes symptoms --> forms psedomembrane

Question 36

Botulium toxin

Answer 36

B = binds A = blocks neuromuscular junction --> no acetylcholine released --> result: flaccid acid

Question 37

Tetroplasmin

Answer 37

B = binds A = blocks GABA at the neuromuscular junction --> spasms 1. lockjaw 2. opithotenas 3. cardiovascular / respitory

Question 38

GABA is responsiable for

Answer 38

relaxation

Question 39

membrane disrupting

Answer 39

- tries to break phospholipid bilayer - cellular components leak out OR - make protein channels

Question 40

process of membrane disrupting

Answer 40

1. hemolysin 2. leukocidin 3. erythrogenic --> scarlet fever --> red skin rash (breakage of blood vessels)

Question 41

Superantigens

Answer 41

- prokokes immune responce - releases cytokines

Question 42

release of cytokines

Answer 42

interlukins --> circulate --> warning in vital sings --> affecs GI tract --> symtoms: nausea, vomitting, diarrhea

Question 43

example of superantigens

Answer 43

s. aureus - TSS - Food posioning

Question 44

vibrotoxin

Answer 44

B=binds A = Gi tract cells -->convert to pumps -->triggers cAMP second system -->rice water stool

Question 45

adherence

Answer 45

- establishes infection - forms route for invasion

Question 46

how does a caspule influence pathogenicity

Answer 46

- evades phagocytosis

Question 47

example of adherence

Answer 47

s. mutans

Question 48

s. mutans

Answer 48

uses capsule + enzyme glucosyltransferase digests sugar (sucrose) -- > converts to: 1. glucose --> enzyme --> glucon --> plaque 2. fractose --> enzyme --> forms acid --> degenerates tooth structure

Question 49

flucon

Answer 49

gummy thin polysaccaride

Question 50

roles of the host

Answer 50

- provides receptors (plasma membrane) --> sugars --> mannose, fructose

Question 51

roles of the pathogen

Answer 51

- has adhesions --> glycoproteins or lipoproteins --> on capsule, flagella, fibrae, M protein, mycolic acid, opa proteins

Question 52

opa proteins are found on

Answer 52

neisseria gonnorhea

Question 53

example of M proteins

Answer 53

s. pyogenes

Question 54

M proteins

Answer 54

- heat and acid resistant - used for attatchement - evades phagocytosis

Question 55

example of glycocalyx

Answer 55

caspule streptococcus mutans

Question 56

example of fimbrae

Answer 56

escherichia coli

Question 57

pathogenicity

Answer 57

the ability to cause disease

Question 58

virulence

Answer 58

the extent of pathogencicty