Hmb Exam 2 Bacterial Pathogenicity And Virulence

Front 1

infectious diseases are complex and involve a series of shifting interaction between _________and____________

Back 1

host and pathogen

Front 2

In a host-pathogen relationship, interaction with regards to pathogen depends on

Back 2

1. pathogens ability to evade or overcome host defense
2. pathogens ability to increase in numbers
3. pathogens ability to identify transmission mechanisms to new hosts

Front 3

In a host-pathogen relationship, interaction with regards to host depends on

Back 3

1. host having useful functioning defenses
2. host's susceptibility to infection
3. degree of compromise found within the host immune system

Front 4

pathogenicity

Back 4

for the pathogen, infection is a matter of survival

Front 5

opportunistic pathogens

Back 5

cause infection by taking advantage of a hosts' increased susceptibility to infection

Front 6

primary pathogens

Back 6

cause disease in healthy individuals

Front 7

characteristics of primary pathogens

Back 7

1. include viruses and bacteria
2. have evolved mechanisms that can overcome host defenses
3. once inside they can multiply rapidly
4. some primary pathogens are restricted to humans

Front 8

pathogenic virulence

Back 8

refers to how harmful pathogen is to host, depends on pathogen's genetic factors - genetic elements are often turned on only in the host

Front 9

pathogens carry virulence genes in clusters called____________

Back 9

pathogenicity islands (can be located on plasmids)
ex. H.pylori

Front 10

plasmids can be transferred between________

Back 10

cells - transfer genetic elements to other bacterial cells

Front 11

biofilms

Back 11

aggregated assemblies fo bacteria formed on a surface in response to various host factors (nutrition, antibiotics, recognition of attachment sites)

Front 12

biofilms consist of________________

Back 12

bacteria and self-produced matrix of extracellular polymeric substance (EPS) - DNA, proteins, polysaccharides

Front 13

characteristics of biofilms

Back 13

differential regulation of genes - immunity to host factors, antibiotics etc.

Front 14

biofilms communicate via________________

Back 14

quorum sensing

Front 15

biofilms are clinically important because

Back 15

1. can capture and retain nutrients (allowing continued growth)
2. they impede uptake of antibiotics and disinfectants
3. inhibit phagocytosis

Front 16

biofilms can build up on medical devices such as

Back 16

catheters
heart valves
prosthetic devices

Front 17

biofilms are one of the causes of ____________on teeth

Back 17

plaque build-up

Front 18

quorum sensing

Back 18

when an organism senses their environment using special sensing proteins

Front 19

bacterial "language"

Back 19

sensor proteins are produced by bacteria, released from bacterial cells and interpreted by other bacterial cells (sensing based on population densities)

Front 20

it is important for the _________of bacteria to communicate and coordinate behavior with members of same species and other species

Back 20

survival

Front 21

certain genes are only turned on when there are enough_________present

Back 21

cells
ex. enterotoxin production in salmonella

Front 22

glycocalyx is sticky substance composed of__________and___________or both

Back 22

polypeptides
polysaccharides

Front 23

glycocalyx is produced in the_____________ and secreted to the outer pat of the______________

Back 23

cytoplasm
cell wall

Front 24

glycocalyx provides a protective element against __________________ and can be used for ________________

Back 24

environmental stress
nutrition

Front 25

Bacterial Cell wall: gram (+) bacteria

Back 25

theichoic acid
lipoteichoic acid
M protein
Mycolic acid

Front 26

theichoic acid (gram positive bacteria)

Back 26

can cause colonization of the nasal epithelium

Front 27

lipoteichoic acid (gram positive bacteria)

Back 27

causes an inflammatory response

Front 28

M Protein (gram positive bacteria)

Back 28

required for infections

Front 29

Mycolic acid (gram positive bacteria)

Back 29

acts as a barrier against antibiotics and host defenses

Front 30

Gram negative cell wall is a complex structure involved in____________in may ways

Back 30

infection

Front 31

outer layer of gram negative cell wal is a barrier to ________________. Porin proteins exclude__________________

Back 31

antiseptics, disinfectants and antibiotics

lage molecules

Front 32

the outer layer (LPS) of the gram negative cell wall functions as endotoxin with 2 parts having clinical relevance:_________________

Back 32

lipid A
O polysaccharide

Front 33

if the glycocalix is loosely attached to the cell wall it is called a __________________

Back 33

slime layer - associated with some forms of dental decay

Front 34

if the glycocalyx is tightly attached to the cell wall it is called a____________________

Back 34

capsule

Front 35

functions of a capsule

Back 35

inhibits phagocytosis
many organisms are not infectious without a capsule
capsule genes can be transferred between organisms

Front 36

both slime layer and capsule variation of glycocalyx give an________________to the organism

Back 36

adherence capability

Front 37

3 structures (outside of bacterial cell wall) are primarily involved with adherence (staying in)

Back 37

glycocalyx
fimbrae
pili

Front 38

2 structures (outside of the bacterial cell wall) are primarily involved with motility (defeating host defenses and damaging host)

Back 38

flagella
axial filament

Front 39

fimbrae and pili

Back 39

involved in adherence
appear as sticky projections (shorter than flagella)
found on gram negative organisms
composed of pilin protein subunits
genes can be transfered from one organism o another

Front 40

flagella used only for ____________

Back 40

motility: make it possible for bacteria to move from their point of origin to other places in the body ex. E. Coli can move from LI (harmless) to urinary tract where it can cause serious infection

Front 41

flagella consists of 3 parts

Back 41

filament - flagellin protein forms twisted helical chain
hook - links filaments to basal body
basal body

Front 42

clinical significance of fimbrae and pili

Back 42

help pathogens fulfill the staying in requirement through adherence

Front 43

fimbrae is only used for adherence, particularly in the_____________and_____________tracts

Back 43

urinary
intestinal

Front 44

pili give bacteria motility in 2 ways

Back 44

twitching or gliding movements
through extension and retraction of pili

Front 45

pili is involved in the development of_______________

Back 45

biofilms

Front 46

pili facilitate the transfer of genetic material from one bacterial cell to another through___________

Back 46

antibiotic resistance
toxin production
defense against host defenses

Front 47

clinical significance of flagella - allow movement which allows___________________

Back 47

opportunistic infections
escape from host defense (defeat host defense)
systemic infection (damage to host)

Front 48

axial filaments

Back 48

flagellum-like structures that are found on spirochets (gram negative bacteria)

Front 49

axial filament wrap around bacterial cell wall and are confined to the space between the_____________and _____________

Back 49

plasma membrane
and the cell wall

Front 50

axial filaments are used for_____________ and cause he entire organism to rotate like a________________

Back 50

motility
corkscrew

Front 51

the corkscrew motion gives the bacterium the ability to bore through____________(staying in). They allow organisms to get into the________ as well as___________ (damage the host)

Back 51

tissue
blood
other tissues

Front 52

six major structures found inside the bacterial cell wall:

Back 52

plasma membrane
nuclear region
plasmids
ribosomes
inclusion bodies
endospores

Front 53

if a bacterium is pathogenic when it undergoes _______________, it will be pathogenic once it emerges

Back 53

sporogenesis

Front 54

endospores are resistant to almost all____________________

Back 54

disinfectants, antiseptics and antibiotics

Front 55

endospores are also resistant to_________ and can cause severe problems for the food industry. ex. ________________

Back 55

heat
Clostridium Botulinum

Front 56

plasmids

Back 56

extra-chromosomal pieces of DNA that are separate from the main DNA structure

Front 57

some bacteria can carry_____________plasmids

Back 57

more than one

Front 58

plasmids often carry __________for toxins and ______________ resistance

Back 58

genes
antibiotic

Front 59

plasmids can be transfered from one cell to another through___________during_______________

Back 59

pili
conjugation

Front 60

lawsuit was filed against maker of_________________chili

Back 60

botulism-tainted

Front 61

bacterial structures that have direct clinical significance

Back 61

cell wall, glycocalyx, fimbrae, pili, axial filaments, flagella and endospores

Front 62

bacterial structures that target antibiotics

Back 62

cell wall, plasma membrane, DNA and ribosomes

Front 63

endospores are formed through the process of ______________

Back 63

sporulation

Front 64

endospores form when a bacterium is exposed to great_________________.

Back 64

environmental stress

Front 65

endospores characteristics

Back 65

1. confer a type of dormancy on the cell
2. extremely resistant to heta, desiccation, toxic chemicals, UV irradiation and antibiotics
3. bacteria can survie for extraordinary lengths of time in endospore state

Front 66

endospore process is restricted to gram__________rods. with one exception:

Back 66

positive
exception: coxiella burnetti (gram negative coccus)