chapter 11 study questions Flashcards
invasion and multiplication of a pathogen in the human host is referrd to as
infection
________ can be characterized by any deviation from the healthy state
disease
pathologic state involving the disruption and destruction of tissues by microbes is referred to as _______ disease
infectious
microbes that are part of the normal microbiota are termed
colonists
laboratory cultivation _______-estimates the # and variety of microbes in the normal microbiota
under
true statements regarding the microbiota
our resident microbes produce enzymes that help us digest food
viruses are found in healthy human in large numbers
while the ______ found on one body site may differ from that found in another location, the ________ profile was similar between body locations
microbiota; protein
correct statements about microbiome in humans
comp of gut biota has an influence on obesity
healthy people have dangerous pathogens, in small amounts
examples of sites that harbor normal microbiota
lungs, mucous membranes, vagina, bladder, urethra, mouth
indicates a relationship in which resident microorganisms prevent the overgrowth of intruder microbes when competing for survival in a common enviro
microbial antagonism
which class are not generally discussed in the context of normal microbiota
viruses
body sites in which microbial DNA has been detected, but microbes have not been definitively observed
blood and brain
disease situations in which a person may be susceptible to infection and disease caused by members of the normal biota
poor hygiene practices allows E. coli to enter urinary tract
immune system is compromised by HIV
microbes enter the blood stream due to injury
what of an infant becomes colonized as it comes in contact with family members
skin, gastrointestinal tract, resp tract, genitourinary tract
broad concept that describes an organisms potential to cause infection or disease is called
pathogenicity
pathogen capable of causing disease in healthy person with normal immune defenses is referred to as
true pathogen
describes the degree of pathogenicity of a microbe
virulence
an infection caused by more than one microbes is
polymicrobial infection
the route a pathogen uses to get into the human host cell is called
portal of entry
a pathogen is a microbe whose relationship with its host is ________ and results in infection and ________
parasitic
disease
infection with a member of normal biota, rather than an agent from the outside, is a _________ infection
endogenous
infection originating from a source outside of the body
exogenous infection
t or f
some pathos can only cause disease if they enter a specific portal of entry
true
the route at which a pathogen enters a host
the gastro tract is the portal of entry for pathogens contained in ____ substances
ingested
an infectious dose is the
minimum number of microbial cells required to cause an infection
t or f
if the inoculum is much larger than the infectious dose, the onset of the disease can be extremely rapid
true
the process by which microbes gain a more stable foothold on host tissues is called __________
adhesion
a pathogen can indirectly damage its host by
inducing excessive immune response
a patho can DIRECTLY damage its host by
secretion of exoenzymes
secretion of toxins
secreted by microbes and breakdown and inflict damage on tissues, dissolve host defense barriers and promote spread of microbes to deeper tissues
exoenzymes
ie. mucinase (digests protective coating on mucous membranes)
hyaluronidase (digests hyaluronic acid that substance that cements animal cells together)
coagulase (causes clotting of blood or plasma)
a chemical called lipopolysaccharide (G-) cell walls; differs from exotoxins because it has a variety of systemic effects on tissues and organs ie. fever, diarrhea, hemorrhage
endotoxin
process by which microbes gain a more stable foothold at the portal of entry through interaction of their molecules with host cell receptors
adhesion
step three of infection
hint: phagocytes
surviving host defenses
substances produced by Streptococcus and Staphylococcus that are toxic to WBCs
leukocidins
three major ways in which microbes damage their host
directly through action of enzymes or toxins (endo and exo)
indirectly by inducing an inappropriate host response
epigenetic changes made to host cells by microbes ie. silencing genes
toxin that generally affects cells by damaging cell membrane and causing lysis or by disrupting intracellular function
exotoxins
microbes enter the body and remain confined to a specific tissue ie. boils, warts
localized infection
infection spreads to several sites and tissue fluids - usually via blood stream -
ie. mumps, rubella, AIDS, syphilis
systemic infection
infectious agent spreads from a (usually asymptomatic) local site and is carried to other tissues
focal infection
a second infection caused by a different microbes which COMPLICATES a primary infection
ie. influenza complicated by penumonia
secondary
infection that comes on rapidly, with severe but short lived effects
acute infection
ie influenza
signs of inflammation
edema (accumulation of fluid in an afflicted tissue)
granulomas and abscesses (walled of collections of inflammatory cells and microbes in the tissues)
lymphadenitis (swollen lymph nodes)
increase in the level of white blood cells is
and decrease in level of WBCs is
leukocytosis
leukopenia
