lesson 1

Question 1

determinants that would influence the outcome of an interaction

Answer 1

host immune system and pathogens’ virulence factors

Question 2

the disturbance in the state of health wherein the body cannot carry its normal function

Answer 2

disease

Question 3

refers to the multiplication of the parasite within the host body

Answer 3

infection

Question 4

means the organism is present on the surface of the skin and mucous membranes

Answer 4

contamination

Question 5

one that harbors parasite

Answer 5

host

Question 6

one that benefits from the symbiotic relationship and harms the host

Answer 6

parasite

Question 7

the capacity of the pathogen to produce disease

Answer 7

pathogenicity

Question 8

pathogenicity of an organism depends on ___

Answer 8

its ability to evade the defense mechanism of the host

Question 9

intensity of the disease produced by the pathogens or the degree of pathogenicity

Answer 9

virulence

Question 10

factors that are produced by a microorganism and evoke disease

Answer 10

virulence factors

Question 11

virulence factors help bacteria to

Answer 11

1. invade host
2. cause disease
3. evade host defenses

Question 12

examples of virulence factors

Answer 12

bacterial toxins and enzymes

Question 13

type of barriers of immune system

Answer 13

physical
innate
specific

Question 14

progression of an infectious disease

Answer 14

incubation
prodromal
invasisve
decline
convalescent

Question 15

period of time beginning with the initial infection through to the point where individual presents clinical signs.

Answer 15

incubation phase

Question 16

The agent localized and begun to multiply; asymptomatic but capable of transmitting the disease agent to others

Answer 16

incubation phase

Question 17

• short and present non- specific mild signs. e.g. redness and swelling, depression and anorexia.

Answer 17

prodromal phase

Question 18

characteristic of a particular disease are apparent

Answer 18

invasive phase

Question 19

signs are at greatest intensity; when pathogen has invaded and damaged host tissues

Answer 19

acme

Question 20

what phasse is acme present

Answer 20

invasive

Question 21

examples of invasive phase

Answer 21

cough, fever, swollen lymph nodes, vomiting, diarrhea

Question 22

characterized by decline in signs associated with the disease

Answer 22

decline phase

Question 23

secondary infection may occur this time as the immune system has been compromised during the interaction with the original pathogen

Answer 23

decline phase

Question 24

host begins to repair the damage caused by the presence of pathogen, and the host recovers.

Answer 24

convalescent phase

Question 25

This phase may be infectious if the disease is associated with scab or accessible lesions.

Answer 25

convalescent phase

Question 26

major virulence factors are

Answer 26

adhesins, capsules and toxins

Question 27

help the bacterium bind to intestinal epithelium,

Answer 27

adhesins

Question 28

2 classification of toxins based on how they are released

Answer 28

exotoxins and endotoxins

Question 29

differentiate endotoxins from exotoxins

Answer 29

exotoxins are soluble substances released in the host tissues while endotoxines are part of the bacterial wall and released when the bacterium dies or divide

Question 30

organisms producing endotoxins and exotoxins

Answer 30

gram negative-endo gram positive- exo

Question 31

location of exotoxins in cells

Answer 31

extracellular, excreted into the medium

Question 32

location of endotoxins in cells

Answer 32

bound within bacterial cell wall. released upon its death

Question 33

chemical nature of exotoxins and endotoxins

Answer 33

exo- polypeptides endo- lipopolysaccharide complex

Question 34

exo and endo stability

Answer 34

exo- unstable(can be natured at 60 C by UV light) endo- relatively stable(can withsatance several hours above 60 C)

Question 35

toxicity of endo and exo

Answer 35

exo-among the most powerful toxins endo- weak but can be fatal in large doses

Question 36

100-1million times as strong as strychnine

Answer 36

exotoxins

Question 37

capsules are prevents phagocytosis

Answer 37

capsules

Question 38

elaboration result to various damaging effects to the host.

Answer 38

toxins

Question 39

exotoxins effect on tissue

Answer 39

highly specific. some act as a neuurotoxins or cardiac muscle toxins

Question 40

fever production exo and end

Answer 40

exo-little or no fever endo- rapid rise in temp to high fever

Question 40

endotoxins effect on tissue

Answer 40

nonspecific. ache all over systemic effects or local site reactions

Question 41

antigenicity of endo and exo

Answer 41

exo- strong. stimulates antibody production and immunity endo- weak. recovery from disease often does not produce immunity

Question 42

toxoid conversion and use endo exo

Answer 42

exo- by treatment with heat or chemicals. toxoid to immunize against toxins endo- cannot be converted to toxoid. cannot be used to immunize

Question 43

examples of exotoxins

Answer 43

botulism, gas gangrene, tetanus, diphtheria

Question 44

endotoxins examples

Answer 44

salmonellosis, tularemia, endotoxic shock

Question 45

the disease triad

Answer 45

host pathogen environment

Question 46

events in all infectious disease

Answer 46

encounter entry and colonization evading host defenses multiplication damage

Question 47

where agents meet the host

Answer 47

encounter

Question 48

after attachments to receptors of host cells by means of specific adhesion molecules present on its surface

Answer 48

entry and colonization

Question 49

proteins that promote tighter binding of bacteria to host cells following initial binding bia pilii

Answer 49

adhesins

Question 50

promotes attachment in small intestine

Answer 50

pili-K88/K99 of e coli

Question 51

mechanisms that destroy host defenses

Answer 51

evading host defense

Question 52

examples of evading host defense

Answer 52

production of extracellular matrices imactivation of cell responses interference with the humoral immune responses

Question 53

ability of organism to invoke deleterious effects

Answer 53

damage

Question 54

how does bacteria damage cells

Answer 54

through toxin production and direct cell and cellular function damage