ch 25 Flashcards
Pathogenicity is the ability
of the pathogen to inflict damage on the host.
Which of the following is not a subunit of lipopolysaccharide (LPS)? A. O-specific polysaccharide B. lipid A C. corepolysaccharide D. M protein
M protein
Diptheria toxin is a A) type of endotoxin. B) cytolytic toxin. C) ABtoxin. D) superantigentoxin
AB toxin.
Decalcification of the tooth enamel is caused by
lactic acid
Tetanus toxin causes
muscles to be unable to relax
Shiga toxin is an enterotoxin that is produced by
Shigella dysenteriae.
The decrease or loss of virulence of a pathogen is referred to as
attenuation.
Which of the following is not important for the adherence of bacteria to host tissues? lipopolysaccharides capsule adhesins slimelayer
lipopolysaccharides
Which of the following is an important factor in the development of dental caries? high salt diet high sugar diet highaciddiet lowsaltdiet
high sugar diet
The spread of pathogens through the blood and lymph systems that results in a bloodborne
systemic infection is called
septicemia.
Which of the following does NOT affect pathogen growth? A) availability of microbial nutrients B) pH C) temperature D) All of these affect growth.
all the above
________ is a damage or injury to a host organism that impairs its function
Disease
Epithelial cells lining the respiratory tract form a
mucous membrane.
What is the difference between adherence and colonization?
Colonization occurs when a microbe begins to grow in host tissues whereas adherence
occurs when the microbe initially attaches.
what is a major growth-limiting micronutrient that influences microbial
growth?
iron
The dose of an antigen that kills 50% of animals in a test group and is used to estimate the
virulence of a pathogen is known as
LD50 (lethal dose)
The best term to describe the general process by which microorganisms cause diseases is
known as
pathogenesis
Septicemia is an example of a
systemic infection
The process by which white blood cells ingest and kill bacteria is called
Phagocytosis
________ are toxic proteins released from the pathogen during normal growth.
endotoxins
________ are microbial infections acquired by hospital patients with noninfectious diseases
because they are compromised hosts.
Nosocomial infections
Pathogenicity pertains to the ability of a pathogen to cause disease.
True
Pathogenicity islands are clusters of genes for virulence factors that are located together on
the bacterial chromosome.
True
An opportunistic pathogen causes disease ONLY in the presence of normal host resistance.
False
Virulence refers to a pathogen’s ability to infect or damage a host.
true
A pathogen’s virulence never changes throughout a host’s life
False
Cholera begins following a bite from a mosquito.
False
Virulence genes may be located on mobile genetic elements
True
Invasion is the ability of a pathogen to enter into host cells or tissues, spread, and cause
disease.
True
The toxic lipopolysaccharides produced by most Gram-negative bacteria are called exotoxins.
False
Gram-positive bacteria produce endotoxins
false
Because malnutrition can make the immune system weaker, the number of Vibrio cholera cells
necessary to produce cholera in an exposed individual is drastically reduced in individuals with
substantial malnutrition.
treu
Diphtheria toxin inactivates elongation factor 2 by catalyzing the attachment of adenosine
diphosphate ribose from NAD+.
true
Clostridium botulinum cannot produce toxins in improperly preserved foods.
false
