Shared Flashcard Set

Details

Micro terms5
chp 5
90
Microbiology
05/31/2011

Additional Microbiology Flashcards

 


 

Cards

Term
need this for successful infection. characteritics that allow the pathogen to thrive and survive in the host's environment
Definition
virulence factors
Term
any point at which an organsim can enter the body is called a _________ and includes:
mucus membranes, skin, and parenteral routes
Definition
portal of entry
Term
the most favorable portal for patheogens. colds, pneumonia, flu, measles and small pox use this portal of entry. productive portal of exiting pathogens
Definition
thge respiratory tract
Term
located in areas adjacent to the outside world. respiratory, gastrointestinal and genitourinary tract. protect against the entry of microorganisms.
Definition
mucus membranes
Term
open to the outside world. microorg can enter via the food and liquids we ingest. includes barriers (to pathogens) like stomach acid and bile..
use this as portal of entry:
polio, hepittis A, Giardia, Vibro cholera, typhoid fever and organisms that cause dysentery
Definition
gastrointestinal tract
Term
the _______________ route of contamination has a major role in infections, especially w/ gram neg bacteria, viruses, protozoa,a dn other parasites
Definition
facal-oral
Term
urinary and reproductive tracts opens to the outside. STDs use this as a portal of entry. once its mucus membrane barrier is broken pathogens gain entry
Definition
genitourinary tract
Term
pathogens enter here through a breech in its surface, hair follicle, or perspiration duct. however each route is very well guarded
Definition
skin
Term
a break in skin barrier portal of entry.
injections and insect bites is an example of this.
plasmodium use this as a way to enter the host
Definition
parenteral route
Term
insect bite entry through the skin
Definition
vector transmission
Term
some gram negative organsims (escherichia coli) uses structures called ____________ to attach to certain receptors on cells of the small intestine, colon and bladder
Definition
fimbrae
Term
in many cases pathogens use molecules called _______, whcih are glycolipids or lipoproteins located on the pathogen surface, as means of adherring to tissue
Definition
adhesins
Term
fluids produced by your oral tissue form a ____________ which is a protein film that coats the teeth
Definition
pellicle
Term
the __________ is th e# of organisms required to kill 50% of the hosts
Definition
lethal dose 50% (ID50)
Term
the ____________ is the # of organisms requirred for 50% of the population to show signs of infection
Definition
infectious dose 50% (ID50)
Term
pathogens w/ the lowest ID 50 and LD50 are the most
Definition
virulent
Term
one of the functions by filling the host cell w/ viral particles called virons until the host cell burst open and pours virions into the intracellular fluid. these viruns locate the new host and repeats this process until there are no more host cells available.
ex: HIV
Definition
lytic virus
Term
pathogen has to deal w/ host defense for success.2 ways: structure of the cell built in ______ defense and the other involves attacking the jost defenses ______
Definition
passive

active defense
Term
the main defenses od pathogenic bacteria are __________ and ______. this is what makes pathogens virulent
ex: S. pneumpniae, haemophilus influenzae, bacillus anthracis, and yersinia paestis can only cause w/ it
Definition
capsules and cell wall components
Term
the 1st line of defense response _______ ingest pathofens then destroy them through adherence which causes the development of pseudopods to surround the organism . encapsulated pathogens arent affected by this
Definition
phagocytosis
Term
the process in which antibody molecules bind to the capsule
Definition
opsinization
Term
the process in which antibody molecules bind to the capsule
Definition
opsinization
Term
when antibody molecules bind to the capsule they attract ____________ cells that use antibody molecules as bridges to adhere to the organism and _____ it
Definition
phagocitic
phagocytose
Term
help increase the virulence of pathogems increasing adherence to host target cells and making the pathogen resistant to heat and acidic environments
inhibit phagocytosis and involved in toxic shock
Definition
M proteins
Term
waxy substance infused to the bac cell wall that inhibitrs phagocytosis and protects the bacterium against antiseptics, disinfectants antibiotics
Definition
mycolic acids
Term
capsules and cell wall components are ___________ measures used to defeat the host defenses
Definition
passive
Term
enzymes that destroy WBCs.
are produced by staphylococoal and streptococcal pathogens
Definition
leukocidins
Term
membrane damaging toxins that disrupts the plasma membrane of the host cells and cause the cells to lyse can damage the plasma membr in red and WBCs n produced by a variety of bacteria:
staphylococal and streptlococal species
Definition
hemolysins
Term
hemolysin produced by streptoccal bacteria is referred to as _________ and can be divided into different groups such as group A and O
Definition
streptolysin
Term
the different types of streptolysin differ from one another in the type of __________.
ex: streptolysin O is associated w/ B-hemolysis
Definition
destruction they cause
Term
a pathogen produced enzyme that causes fibrin clots to form in the blood of the host. used by both host an dpathogen during infection
Definition
coagulase
Term
enzymes that break down fibrin and dissolve clots. used by the pathogen to overcome attempts by the host to wall off infection, thereby ensuring spread
Definition
kinases
Term
enzymes that break down connective tissue and collegen in host, thereby allowing infections to spread
ex: gas gangreene
Definition
hyaluronidase and collagenase
Term
process in spreading important for increased virulence. enzymes inhibits the clotting machinery or to breakdown clots formed by the host, allowing the pathogen to spread.
ex: strep throat (minor) necrotizing facitis (major)
Definition
group A streptocci
Term
able to survive in only one type of environment
Definition
obligate
Term
salmonella produces a molecule called _______ that changes the structure of the actin filaments in the cytoskeleton. this changes moves the bac in the cell. the pathogen moves the actin filaments from place to place inside of the cell.
Definition
invasin
Term
the host cell can also use a host cell molecule called ____ to move from one cell to another w/ out ever exposing itself to the immune defenses searching for it
Definition
cadherin
Term
the major portals of entry are the
Definition
mucus membranes, skin and parenteral routes
Term
_____ portals of entry are associated w/ the respitory, digestive and genitourinary tracts of the body
Definition
mucus membrane
Term
can be accomplished using adhesion molecules, which are glyco lipids or lipoproteins.
Definition
establishment (stayin in requirment)
Term
some pathogens take advantage of structures auch as ____ to adhere to tissue
Definition
fimbrae
Term
most damage associated w/ infection can be divided up into 2 parts
Definition
damage that occurs because the bacteria is present
damage that is a by product of the host's response
Term
obvious destruc of host cells and tissues
usual localized to site of infection
defense response is timely and potent, ususally limiting the damage done
Definition
direct damage
Term
seen in most serious infections
dangerous to host due to cause systemic disease
results in production of bacterial toxins
Definition
indirect damage
Term
are soluable in aqueous solution s and easily diffuse into and moove through the blood and lymph systems. causes pathogenic sites to be far from the inital infec site
Definition
bacterial toxins
Term
produced by pathogen and enter host cells
most lethal
enzymatic protein soluable in the blood or lymph
diffuse in tissues and stop metabolic func of cell
Definition
exotoxins
Term
many exotoxins are very dangerous and are usually produced by pathogens in ___________ form which inactive than activated after having left the pathogens cells
Definition
proenzyme
Term
many genes that encode exotoxins are carried on _____ in the pathogens, which makes it possible to transfer genetic info from one bacterium to another
Definition
plasmids
Term
there are 3 types of exotoxins
Definition
cytotoxins, neurotoxins and enterotoxins
Term
kills cells in which they come in contact w/
Definition
cytotoxins
Term
interfere w/ neurological signal transmission
Definition
neurotoxins
Term
affect the lining of the digetive system
Definition
entertoxins
Term
is a cytotoxin
produced by bacillus anthracis
increases vascular permebility
hemmorhage and pulmonary edema results
Definition
anthrax (
Term
a cytotoxin
produced by the corynebacterium
inhibits protein synthesis
leads to heart damage, possible death weeks after apparent recovery
Definition
diptheria toxin
Term
a neurotoxin
produced by clostridium botulinum
blobks the release of acetycholine
leads to respitory paralysis
Definition
botulinum toxin
Term
a neurotoxin
produced by clostridium tetani
inhibits motor neuron antagonist
vauses violent skeletal muscle spasms (lock jaw)
and respiratory failure
Definition
tetanus
Term
enterotoxin
produced by vibrio cholerae
causes excessive loss of water and electrolytes
severe diarherra; death can occur w/in hours
Definition
vibrio
Term
bac staphylococcus aures produces an enterotoxin that affects the digestive system and cause this
loss lots of liquid from body which cause of death
Definition
toxic shock
Term
after inactivation treatment, toxins are referred to as
Definition
toxoids
Term
are bacterial toxins that are part of the cell wall of gram negative bacteria. active after a bacteria containing them has been killed. leave the dead cell wall and enter the blood stream of the infected host
Definition
endotoxins
Term
endotoxins are a component of gram neg organisms
are part of the bacterial cell wall
symptoms: fever, chills, muscle weakness, and aches
lareg amounts can cause shock and diseminated intravascular cloting
Definition
endotoxins
Term
are produced by gram positive organisms
Definition
exotoxins
Term
have an outter layer made up of lipoproteins, phospholipids, and lipopolysacharides. while the organism is alive the outter layer stays in place but when it dies the layer falls apart. lipopolysaccharides of this layer contain a particular lipid called lipid A which have endotoxin properties
Definition
gram negative bacteria
Term
condiotn in which minor clotting occurs throughout the body. this uses up clotting elements so they arent avail when needed
Definition
disseminated intravascular clotting
Term
almost all gram positive
located extracellular, excreted by living organisms
is a polypeptide
among most powerful toxins
highly specific, several types
no fever production
very good as an antigen, long lasting immunity conferred
conversion to toxoid form by chemical treatment
lethal dose is small
unstable; @ high temp
Definition
exotoxins
Term
diseases asociated:
botulism, gas gangreene, tetanus, diphtheria, cholera, plague, scarlet fever, staphylococcol food poisoning
Definition
exotoxins
Term
almost all gram negative
location: part of pathogen cell wall, released when the cell dies
is made of a lipopolysaccharide complex
stable; can w/ stand high temp 4 hrs
nonspecific, local reactions such as fever, aches and possible shock
rapid rise to very high fever
weak usefulness as an antigen; no immunity conferred
lethal dose is large

Definition
endtoxins
Term
ex:
salmonelosis, typhoid fever, tularemia, meningococal menigitis, endotoxic shock
Definition
endtoxins
Term
a test to determine if theres an endotoxin contamination of supplies and equipment. takes advantage of the WBCs of the horse shoe crab
Definition
limulus amebocyte lysate assay
Term
in the presence of endotoxin its WBCs clot into a gel like matrix that becomes cloudy (turbid). the degree of turbidity can be used as a measure of the amount of endotoxin contamination present
Definition
limulus
Term
damage to the host can either be direct or indirect. direct damage is usually __________ and indirect damage is usually through the production of ______
Definition
localized
toxins
Term
are extremely lethal substances produced by living cells (usually gram positive) and in most cases proteins
can cause the production of antibody
Definition
exotoxins
Term
are contained inside the bacterial wall and released when the cell dies
are products of gram negative organisms, dont effectively generate antibody, less toxic
Definition
endotoxins
Term
Lipid A which is part of the gram negative phospholipid outter layer of the bacterial cell wall has
Definition
endotoxin properties
Term
virually caused cell death or damage is a
Definition
cytopathic effect
Term
(cytopathic effect)
cytopathology associated w/ viral infections can occur in 3 ways
Definition
viral overload
cytocidal effect
non-cytocidal effect
Term
(cytopathic effect)
causes the virus to explode out of the host cell and infect and lyse surrounding host cells
Definition
virla overload
Term
(cytopathic effect)
when the host defense mech identify and kill virally infected cells
Definition
cytocidal effect
Term
(cytopathic effect)
occurs when a virus shuts down the host DNA, RNA, and protein synthesis and thereby forces the host cell to devote all its efforts to virus production
Definition
non- cytocidal effect
Term
inclusion bodies seen in rabies viral infections and can be diagnostic for this disease
Definition
negri bodies
Term
gigantic cells formed as a # of infected host cells merge; can also be a visual identification of viral infection
Definition
synctia
Term
use an array of virulence factors including capsules, M proteins, mycolic acids, leukocidins, hemolysin, coagulase, kinases, hyaluronidase, and collagenase
Definition
to avoid being killed by the host defenses pathogens
Term
pathogens use ___________ such as __________ to establish themselves in the host
Definition
virulence factors
adhesions
Term
a micro is infecting via the parenteral route. what does that mean
Definition
it entered through a break in the skin
Term
using fimbrae to attach to a receptor, releasing several exotoxins to destroy the host cell. \using adhesions to attach to tissues
creating a biofilm on the body's surface
Definition
all have a role in establishment
Term
a bacterial enzyme that breaks down connective tissue
Definition
hyaluronidase
Term
changes the structure of actin filaments in the host cell
Definition
invasin
Term
you have a culture of cells that are producing exotoxins. the cells are probably
Definition
gram positive bacteria
Term
toxins found on gram negative cell walls
Definition
endotoxins
Term
a patient has disseminated intravascular clotting, the patients disease is caused by
Definition
endotoxins