Exam One Flashcards
(134 cards)
1
Q
free living bacteria
A
can live in environment. no importance for animals and disease
2
Q
symbionts
A
bacteria and host living together
3
Q
obligate symbionts
A
must have a host
ex: intracellular bacteria
4
Q
facultative symbionts
A
can have a host, but is not necessary
5
Q
mutualism
A
both are necessary and relation is positive for both
6
Q
commensalism
A
good for one, not a problem for the other
7
Q
parasitism
A
one takes advantage of the other
8
Q
facultative pathogenic
A
can cause infection in the right condition
9
Q
endogenic infection
A
bacteria come from within the body. only under certain conditions do the bacteria cause infection
10
Q
exogenic infection
A
get bacteria from environment, other animal, etc.
11
Q
obligate pathogenic
A
it will cause disease if it infects a host
12
Q
balanced pathogenicity
A
damage with recovery
13
Q
unbalanced pathogenicity
A
do not recover completely, or death
14
Q
infection
A
invasion and multiplication of micro-organism, eventually with disease
15
Q
disease
A
structural and functional damage
clinical/subclinical
opportunistic- certain conditions
septicemia/bactermia- blood infection
16
Q
flagella
A
used in motility
antigenic - use in vaccinations
not in all bacteria, mainly in gram negative
long, filamentous protein structures
17
Q
pili
A
adhesion or bacterial interaction
F-antigens, antigenic
18
Q
sex pili
A
used for bacterial conjugation and plasmid transfer
19
Q
how do bacteria cause disease
A
adhesion, invasion, toxin release
20
Q
invasion - immunological reaction
A
then pathogenicity you see is from the immune reaction rather than the actual bacteria
21
Q
capsule
A
not in all bacteria polysaccharides - proteins environmental protection capsular antigens iron uptake - helps bacteria evade immune system, prevent phagocytosis - aids in attachment to surfaces - increased tolerance to antimicrobial agents
22
Q
exotoxins
A
injection of toxins being put into cell by bacterium during toxin release
- bacterial metabolites
23
Q
Type I exotoxins
A
bind receptor, disturbance of cell metabolism
24
Q
Type II
A
cell wall damage
25
Type III
intracellular toxins. binds cell wall, goes intracellular
26
Endotoxins
gram negatives
Lipid A is endotoxin of the LPS
cell wall components
27
function of LPS
protection against toxic products and complement immune system
act as endotoxin - infection with a gram negative bacterium
28
anatoxins
chemically treated toxins.
| toxicity has diminished, antigenicity has increased
29
two main secretion systems of bacteria
porin
injection system
- release proteins into environment or host. secreted proteins are typically related to virulence or bacterial communication
30
membrane vesicles
lipid membrane
contain enzymes, exotoxins, DNA, signal molecules
role in pathogenesis, signaling, excretion, immunomodulation, transformation. consume antibodies, expel complement factors.
31
biofilms
formed in nutrient poor environments to protect from environment. also protects from host immune system. release bacteria periodically, indicative of chronic disease.
made of polysaccharides, proteins, nucleic acid
32
(lipo)proteins - porins
role in iron uptake. no free iron because body sequesters it. pathogenic bacteria circumvent iron restriction by replacing it with manganese. can cause septicemia
33
4 things that eukaryotes and prokaryotes have in common
cell membrane
cytoplasm
DNA
ribosomes
34
major difference between eukaryotes and prokaryotes
eukaryotic cells have membrane enclosed organelles
35
cytoplasm
macromolecules: proteins, mRNA, tRNA
small molecules: energy sources, precursors of macromolecules, metabolites, or vitamins
inorganic ions: required for enzymatic activities
function: help facilitate chemical reactions, dissolve solutes
36
nucleoid
contains DNA, proteins, RNA
bacterial chromosome, circular DNA macromolecule
organization and expression of bacterial genome
37
plasmid
composed of DNA, separate from nucleoid
often contains genes important for virulence and resistance (survive under antibiotics)
conjugation: plasmid can transfer cell to cell
38
what is the function of the capsule and cytoplasmic membrane?
protection from environment
39
cell envelope
```
cytoplasmic membrane
cell wall - peptidoglycan layer
periplasmic space
outer membrane (gram -)
capsule
```
40
gram negative bacteria
outer and cytoplasmic (inner) membrane
thin layer of peptidoglycan
LPS in outer membrane
stain pink
41
gram positive bacteria
```
cytoplasmic membrane (inner)
thick layer of peptidoglycan
teichoic acids attached to peptidoglycan
stain purple
```
42
mycobacteria
similar to gram+ but contains mycolic acid attached to peptidoglycan
creates waxy shell, more resistant to staining and the environment
43
mollicutes
only has a cytoplasmic membrane that contains sterols
| does not have peptidoglycan layer (cell wall)
44
cytoplasmic membrane
composed of phospholipid bilayer and proteins
inner most membrane next to cytoplasm
hydrophobic molecules passively diffuse
key role in energy generation (proton motive force) and bacteria respiration (electron transport chain)
45
peptidoglycan layer (cell wall)
protects cell from osmotic lysis and provides mechanical protection
consists of polymers of disaccharides that are cross-linked with short chains of amino acids (peptides) by penicillin-binding proteins
46
outer membrane
protective barrier
only present in gram negative bacteria
asymmetrical lipid bilayer composed of LPS in the outer membrane to prevent diffusion of hydrophobic compounds
porin proteins allow small hydrophilic molecules to passively enter cell
- provides resistance to toxic compounds that are hydrophobic or large
47
endospores
dormant bacteria that can survive in adverse environmental conditions and for long periods of time.
when endospores enter a host, they can revert to their active state, multiply and cause disease
48
obligate aerobes
need oxygen to survive
49
obligate anaerobes
cannot survive in oxygen
50
facultative anaerobes
can survive without oxygen, but prefer it
51
aerotolerant anaerobes
do not use oxygen but are not affected by its presence
52
antibiotic
produced by natural microorganisms
selective toxicity
can inhibit the growth or kill microbes
53
antimicrobial/antibacterial
any substance of natural, semisynthetic, or synthetic origin that kills or inhibits the growth of microorganisms/bacteria but causes little or no damage to host
54
all antibiotics are __________, but not all _______ are antibiotics
antimicrobials
55
therapeutic antimicrobial use
when diseased animals are treated to cure infection
56
prophylactic antimicrobial use
when healthy hers or animals are treated to prevent infection
57
metaphylatic antimicrobial use
when diseased herds are treated to cure infection in some individuals and prevent infection in others
58
growth promotion antimicrobial use
when healthy animals re treated with sub-therapeutic concentrations to improve growth rate and efficiency of feed utilization and improve reproductive performance
59
classification of antibacterial agents
```
chemical structure
origin
effect on bacteria
spectrum of activity
mode of action
```
60
naturally produced antibacterial agents
produced by fungi and bacteria (antibiotics)
61
semi-synthetic antibacterial agents
chemically altered natural compound
62
synthetic antibacterial agent
chemically designed
63
bactericidal
kill bacteria
64
bacteriostatic
inhibit growth of bacteria
65
some drugs may be bactericidal or bacteriostatic depending on:
drug concentration
presence of other drugs
bacterial species - gram- vs gram+
66
narrow spectrum
have activity restricted to few bacterial groups
67
broad spectrum
have activity against a wide range of different bacterial organisms
68
MOA - cell wall synthesis
betalactams, penicillins
69
MOA protein synthesis
gentamicin, tetracyclines
70
MOA DNA synthesis
fluoroquinolones
71
MOA cell membrane integrity
polymyxins, colistin
72
MOA folic acid synthesis
sulfonamides
73
beta-lactams
penicillins
cephalosporins
carbapenems
74
penicillins
```
bactericidal
beta-lactams
penicillin G/V
ampicillin/amoxicillin
amoxicillin/clavulanic acid
```
75
cephalosporins
```
bactericidal
beta-lactams
Cefalexin / Cephadroxil
Cefpodoxime / Ceftiofur
Cefovecin, Cefquinome
```
76
carbapenems
beta-lactems
Imipenem / meropenem
Ertapenem / doripenem
bacteriostatic
77
tetracyclines
tetracycline
oxytetracycline
doxycycline
bacteriostatic
78
quinolones
synthetic, bactericidal
oxolinic acid
Enrofloxacin / Marbofloxacin
Pradofloxacin / Norfloxacin
79
sulfonamids
synthetic
sulfadiazine
sulfadiazine/trimethoprim
bacteriostatic
80
phenicols
chloramphenicol
elorfenicol
bacteriostatic
81
macrolides
erythromycin
tiamulin/ tilmicosin
bacteriostatic
82
lincosamides
lycomycin/clindamycin
| bacteriostatic
83
aminoglycosides
bactericidal
streptomycin
gentamicin/neomycin
amikacin
84
polypeptides
colistin/polymixin
| bacteriostatic
85
miscellaneous
metronidazole
| bacteriostatic
86
glycopeptides
bactericidal
| vancomycin/teicoplanin
87
oxazolidinones
linezolide
| bacteriostatic
88
parasite
a smaller organism that lives on or in and at the expense of a larger organism, the host
89
3 main classes of parasites that can cause disease:
helminths
ectoparasites
protozoa
90
nematodes (roundworms)
free-living or parasitic
elongate/cylindrical
alimentary canal present
sexes usually separate
91
cestodes (tapeworms)
flat body
no alimentary canal - absorbs its nutrients
scolex - head has suckers that allow it to stay in the host
strobili (body) with proglottids - segmented body that each has its own hermaphroditic reproductive organs
92
trematodes (flukes)
leaf-like
| oral and ventral suckers
93
insects
flies, fleas, lice, hemiptera (bed bugs)
adults have 3 pairs of legs
head, thorax, abdomen, antenna
94
arachnids
ticks, mites
4 pairs of legs
has palps on outer part of mouthpiece, used to anchor mouth piece to host
95
protozoa
unicellular, eukaryotic animals (have true nucleus)
| classified by locomotion accomplished by: pseudopodia, cilia, flagella, gliding movement
96
ectoparasites
lives on the host, causes infestations
97
endoparasites
lives in the host, causes infections
98
definitive host
harbors adult or sexual stage of parasite
99
intermediate host
harbors larval or asexual stage of parasite
100
incidental host
an unusual host, unnecessary for maintenance of parasite in nature
101
common routes for parasite entry
```
ingestion
skin or mucosal penetration
transplacental (prenatal)
transmammary (milk)
arthropod bite (vector)
sexual contact
```
102
mechanical damage (parasites)
blockage of internal organs
pressure atrophy
migration through tissues
103
toxic products of parasites
destructive enzymes
endotoxins
toxic secretions
104
toxocariasis
inflammation causes pathology during worm migration
105
all viruses are _____ parasites
obligate
106
capsid
protein shell of a virus that encases/envelopes the viral nucleic acid or genome
- made of capsomeres held together by non-covalent bonds
107
nucleocapsid
capsid + virus nucleic acid
108
lipid envelope
some viruses have this additional layer that covers the capsid
- lipid bilayer derived from the host
109
glycoproteins
present on the surface of the envelope, appear as spikes
110
naked viruses
have only protein capsid enclosing nucleic acid
111
pleomorphism
ability of some viruses to alter their shape or size
112
virus replication
1. attachment
2. penetration
3. uncoating
4. synthesis of viral nucleic acid and protein
5. assembly and maturation
6. release in large numbers
113
impact of virus replication in host cell
cell death (lysis, apoptosis)
no apparent change
transformation of cell to malignancy
fusion of cells, multinucleated
114
direct-contact transmission
direct physical contact with infected/susceptible host
115
indirect-contact transmission
contaminated inanimate objects
116
common-vehicle transmission
fecal contamination of water or food and virus contamination of meat or meat products
117
vertical transmission
infection that is transferred from mother to embryo, fetus, or newborn before, during, or shortly after parturition
118
antiviral drugs
interfere with the ability of the virus to infiltrate a target cell or target different stages of replication/synthesis of components required for replication of virus
119
immune system stimulation
interferons, class of proteins that has antiviral effects and modulate functions of the immune system
120
vaccination
live-attenuated virus
non-replicating virus
produced by recombinant DNA and related technologies
121
biologic control of arthropod vectors
use of predatory fish to control mosquito population for example
122
chemical control of arthropod vectors
use of insecticides
123
pathogenicity
ability of virus to cause disease in a host
| yes/no question
124
pathogenesis
manner/mechanism of development of a disease
125
virulence
used as a quantitative or relative measure of the degree of pathogenicity of the infecting virus
126
disseminated infection
infection spreads beyond the primary site of infection
127
systemic infection
if a number of organs or tissues are infected
128
neurotropic virus
viruses can infect neural cells. infection may occur by neural or hematogenous spread
129
neuroinvasive virus
viruses that enter the CNS after infection of a peripheral site
able to cross BBB
130
neurovirulent virus
viruses that cause disease of nervous tissue, manifested by neurological symptoms and often death
131
viral tropism
the specificity/affinity of a virus for a particular host tissue
132
viremia
presence of virus in blood
133
primary viremia
initial entry of virus into blood
134
pantropic viruses
can replicate in more than one host organ/tissue
