Bacteriology - Exam 2 Flashcards
bacteria basic characteristics
single cell, prokaryotic, no nucleus, binary fission, 70s ribosomal unit, classified by 16s
shapes for: cocci, bacillus, helical, curved, staph, strep
round, rod, spiral, coma, grape cluster, chain
gram positive bacteria
thick, lipoteichoic acid (antigenicity), stain blue
gram negative bacteria
thin, LPS (virulence), stain pink
mycobacteria contributes to
virulence
endotoxin
only gram negative, Lipid A component & polysaccharide component
Lipid A component of endotoxin contributes to
activation of immune system, harmful effects on host
polysaccharide component of endotoxin contributes to
antigenicity
acid fast positive stains
pink (mycolic acid)
acid fast negative stains
blue
monotrichous flagella
one end
amphitrichous flagella
both ends
lophotrichous flagella
multiple from one end
peritrichous flagella
all sides
endoflagella
from within, spirochetes
pili/fimbriae used for
adherence, antigenicity
K88
pig
K99
cow
capsule function
stick cells together, food reserve, protection, evade phagocytosis
endospore characteristics
gram positive, resistant, live even through bad conditions
examples of endospores
clostridium, bacillus
O2 required in
aerobic, microaerophilic, capnophilic
O2 utilized in
facultative anaerobes
O2 neither required NOR utilized in
obligate anaerobes or aerotolerant anaerobes
pathogen has the potential to
cause disease
7 host characteristics
breed, age, sex, genotype, immunity, physiology, damage
9 pathogen characteristics
type, genotype, survival, virulence, route, tropism, dose, resistance, vector
7 environment characteristics
housing, space, ventilation, hygiene, nutrition, disease control, survival
infection definition
invasion/multiplication in host/population
disease definition
infection causes damage to vital functions
5 examples of portals of entry
skin, mucous membranes, respiratory tract, GI tract, urogenital tract
exotoxin characteristics
proteins released to outside to specific target cells
endotoxin characteristics
gram negative, induce inflammation, heat stable
superantigen characteristics
made by viruses/mycoplasma/bacteria to bind to MHC II on antigen presenting cells & T helper cells to release cytokines
biofilm, quorum sensing, fimbrae, flagella, capsule increase
virulence (can carry genes for antibiotic resistance, movement, protection, etc.)
biofilm example
dental plaque
how does quorum sensing work
certain population reached -> change behavior -> ambush immune system
plasmids
small, circular DNA
examples of plasmids
tetanus & staph (superantigens)
bacteriophages
virus that attack bacteria
examples of bacteriophages
diphtheria, shiga, botulinum
virulence is the degree of
pathogenicity (+/- severity)
virulence transferred by conjugation
transfer genetic material through direct contact through pilus
virulence transferred by transformation
exogenous genetic material taken in
virulence transferred by transduction
DNA transferred between a bacteria & virus
obligate pathogen numbers, predisposition, virulence, disease type
numbers don’t matter, doesn’t need to be predisposed, very virulent, causes distinct disease
primary pathogen disease type
distinct
opportunity pathogen disease type
nonspecific
nonpathogen numbers, predisposition, virulence, disease type
lots of numbers, does need to be predisposed, virulence doesn’t matter, causes nonspecific disease