Introduction to Infectious Diseases Microbes and Microbial Morphology

Question 1

pathogen

Answer 1

any disease-causing microorganism

Question 2

primary pathogen

Answer 2

cause disease in any host

Question 3

opprotunistic pathogens

Answer 3

can only cause disease in hosts with impaired or damaged defense mechansisms

Question 4

infection

Answer 4

microorganism penetrates body surfaces, enters host tissue, multiplies, damages tissues, causes host to react with immune response

Question 5

virulence

Answer 5

ability of organism to cause disease

Question 6

avirulent

Answer 6

organism which cannot cause disease

Question 7

virulence factors/determinants

Answer 7

properties or gene products of microorganisms that enhance their disease-producing capabilities

Question 8

examples of virulence factors/determinants

Answer 8

colonization
invasion
tissue damage

Question 9

asymptomatic carriage

Answer 9

state where infection exists with no clinical symptoms

Question 10

famous example of asymptomatic carriage

Answer 10

typhoid mary

Question 11

colonization

Answer 11

establishment of microbial growth on body surface

Question 12

humans are exposed to potentially disease-causing agents from 3 general sources:

Answer 12

exogenous microbes: human to human
exogenous microbes: animal to human
endogenous agents: normal flora

Question 13

What are 4 types of transmissions for human to human

Answer 13

respiratory
salivia
fecal-oral
venereal

Question 14

Zoonotic infections

Answer 14

animal to human transmission

Question 15

vector ( biting athropod) ex.

Answer 15

ticks spread Rocky Mountain Spotted Fever

Question 16

vertebrate reservoirs ex.

Answer 16

dogs and bats spread rabies

Question 17

vector-vertebrate reservoir ex.

Answer 17

bubonic plaque spread from rats to fleas to man

Question 18

fomites

Answer 18

inanimate objects which harbor microorganisms

Question 19

nosocomial infections

Answer 19

impaired defense system, poor sanitation in hospitalized patients

Question 20

3 cases where disease results from microbe’s ability to alter normal immune response

Answer 20

autoimmunity
superantigens
septic shock

Question 21

autoimmune activation

Answer 21

pathogen produces protein similar to host protein ( cross-reactive material), causes host to attack itself

Question 22

superantigens

Answer 22

elaboration of superantigens which result in the activation of many T cells

Question 23

when does normal flora become a source of infection

Answer 23

microorganism move from normal habitat and invade areas which are sterile or devoid of organism in question

Question 24

sterile tissues

Answer 24

microorganisms typically laden absent

Question 25

example of sterile tissue

Answer 25

blood alveoli muscle

Question 26

where are normal flora generally laden with microbes

Answer 26

external surfaces, | skin, GI, upper respiratory

Question 27

going through GI system, what general patterns seen

Answer 27

increase number organisms increase types of species increases frequency of species

Question 28

4 beneficial effects of normal flora

Answer 28

production of vitamin K occupy Niche elaboration of bacterial toxins ( kill potential pathogens) stimulate immune response

Question 29

bacteriocins

Answer 29

toxic bacterial proteins that kill other bacteria

Question 30

what are 3 mechanisms for opportunistic infection to present

Answer 30

compromised hosts breach of host surfaces use of antibiotics

Question 31

how can host be compromised for an opportunistic infection

Answer 31

``` age cancer nutritional status inherited immune deficiencies immune suppressive agents HIV ```

Question 32

how does opportunistic infection enter host through breach of normal barriers

Answer 32

cuts, surgery burns medical devices

Question 33

How can use of an antibiotic allow opportunistic organism proliferate

Answer 33

antibiotic wipes out normal flora

Question 34

name 4 postulates for Koch's postulates

Answer 34

1) bacterium should be found in all suffering organisms 2) bacterium isolated and cultured 3) reproduce disease when bacterium enters another organism 4) bacterium isolated and must be same to original bacteriam

Question 35

limitation to #1 of Koch's postulate

Answer 35

human susceptibility to disease may be inherited and so hosts may not be susceptible

Question 36

limitation to #2 of Koch's postulate

Answer 36

late onset (slow virus)

Question 37

limitation to #2 and 3 of Koch's postulate

Answer 37

fastidious organisms are harder to culture, some can't be cultured at all

Question 38

limitation to #4 of Koch's postulate

Answer 38

ethical issues

Question 39

polymicrobial infections

Answer 39

disease caused by combination of pathogens

Question 40

name 2 genreal limitations to Koch's postulates

Answer 40

variability in virulence | polymicrobial infections

Question 41

prokaryotes

Answer 41

cells lack a membrane bound nucleus

Question 42

eukarytoes

Answer 42

cells with defined nucleus

Question 43

bacteria

Answer 43

unicellular prokaryotic organisms | lack nuclear envelope and membrane-bound organelles

Question 44

fungi

Answer 44

eukaryotic organisms | defined nucleus, membrane bound cytoplasmic organelles and cell wall

Question 45

yeast

Answer 45

unicellular

Question 46

mold

Answer 46

mutlicellular and filamentous

Question 47

dimorphic fungi

Answer 47

switch from yeast to mold

Question 48

name 3 groups in fungi

Answer 48

yeasts molds dimorphic fungi

Question 49

parasites (broad definition)

Answer 49

prokaryotic, eukaryotic or viral organism require a living host for at least part of their life cycle cause disease to host

Question 50

parasites ( narrow definition)

Answer 50

any unicellular or mutlicellular eukaryotic organisms that require loving host for at least part of their life cycle and cause disease to host

Question 51

virusus

Answer 51

intracellular parasites lack cell structure | require host for cellular replication

Question 52

what do viruses generally consist of

Answer 52

nucleic acid genome surrounded by protein coat

Question 53

site of cellular respiration in prokaryotes | eukaryotes

Answer 53

cell membrane | mitochondria

Question 54

parasites ( narrow definition) excludes what organisms

Answer 54

viruses and bacteria

Question 55

translation begins with what in eurkaryotes? prokaryotes

Answer 55

methionine | N-formylmethionie

Question 56

what does host cell provide virus

Answer 56

proteins involved in DNA replication, translation, transcription

Question 57

Name 2 types of viral infection

Answer 57

lytic cycle | persistent or latent

Question 58

lytic cycle

Answer 58

virus invades cells, virus replicates, lyse host cell to release all of the viruses

Question 59

persistent or latent infections

Answer 59

host cell harbors viral genome or allow replication of low number of viruses

Question 60

lysogeny

Answer 60

bacteriphage lie dormant within the host bacterium

Question 61

genome of virus can be

Answer 61

either DNA or RNA (not both)

Question 62

capsid

Answer 62

primary outer structure composed of protein of virus

Question 63

name two organisms that are simpler than viruses

Answer 63

viroids | prions

Question 64

viroids

Answer 64

RNA genome without protein components

Question 65

prions

Answer 65

infectious agents consisting only of protein