Microbiology Chapter 35
Suppose a student infected with influenza virus is sitting three feet across from you in class, coughing frequently. You do not touch the student or share any items with her. A few days later, you come down with influenza. What was the most likely route of transmission? Multiple choice question. airborne direct contact vertical vehicle
airborne
Antitoxins are ______. Multiple choice question. complement molecules that are activated by toxins T cell receptors that bind to toxins antibodies that inactivate toxins cytokines that stimulate antitoxin immunity
antibodies that inactivate toxins
Antibodies that recognize and inactivate bacterial exotoxins are generally called _____________.
antitoxins
Select the best definition of pathogen. Multiple choice question. the ability of an organism to cause disease any microscopic organism any microscopic organism that causes disease any organism that causes disease
any organism that causes disease
In an AB exotoxin molecule, the B portion ______. Multiple choice question. binds to the target receptor on a host cell dramatically stimulates a large portion of circulating host T cells, causing them to inappropriately secrete cytokines is a component of the bacterial outer membrane achieves the negative effect of the toxin inside the cell after it gains entry
binds to the target receptor on a host cell
Bacteria such as Streptococcus pneumoniae and Haemophilus influenzae resist phagocytosis by producing an outer mucoid structure called a(n) ______________________.
capsule
Influenza Virus
changes surface proteins by genetic recombination
The term that most specifically describes the establishment of a site of microbial replication on or within a host is ______. Multiple choice question. colonization infection virulence adherence
colonization
When a microorganism establishes a site on or within a host allowing replication, _____________ has occurred.
colonization
Select all correct descriptions of lipid A (endotoxin). Multiple select question. component of the outer membrane of Gram-negative bacteria produced by Gram-positive bacteria only weakly immunogenic secreted by living bacteria heat stable
component of the outer membrane of Gram-negative bacteria only weakly immunogenic heat stable
Superantigens cause disease by ______. Multiple choice question. dramatically stimulating a large portion of circulating host T cells, causing them to overexpress and release cytokines achieving the negative enzymatic effect of the toxin inside the cell after it gains entry failing to stimulate any immune response by the host forming pores in the plasma membrane of target cells, destabilizing membranes and lysing cells
dramatically stimulating a large portion of circulating host T cells, causing them to overexpress and release cytokines
Lipopolysaccharide (LPS) is also called because it is bound to the outer membrane of Gram-negative bacteria, and it is harmful to humans.
endotoxin
Among the most lethal substances known, heat-labile proteins secreted mainly by Gram positive bacteria are called ______. Multiple choice question. venoms exotoxins antitoxins endotoxins
exotoxins
S. pyogenes
expresses m protein on their surface to prevent detection
Microbial pathogens that only grow and replicate outside of a host cell are typically called ________ pathogens.
extracellular
True or false: Bacterial endotoxins produced by different species have very distinct structures and produce variable effects on different target cells. True false question.TrueFalse
false
Select three signs (as opposed to symptoms) of an infectious disease. Multiple select question. fever pain blood in the stool rash loss of appetite
fever blood in the stool rash
Select three signs (as opposed to symptoms) of an infectious disease. Multiple select question. loss of appetite fever pain blood in the stool rash
fever blood in the stool rash
The best term to describe an inanimate vehicle (e.g. surgical instrument, bedding, or drinking vessel) that can spread a pathogen to multiple hosts is a ______. Multiple choice question. fomite trojan horse vector mechanical vector
fomite
Select all that apply Select all correct descriptions of bacterial exotoxins. Multiple select question. most cause a general shock-like syndrome heat-labile (inactivated at 60-80 degrees C) among the most toxic substances known a component of the microbe itself; not secreted often encoded on plasmids or prophages
heat-labile (inactivated at 60-80 degrees C) among the most toxic substances known often encoded on plasmids or prophages
The spread of a pathogen via some type of contact between two individuals is generally called ___________ transmission, whereas _________________ transmission occurs when an unborn child acquires a pathogen from an infected mother.
horizontal, vertical
An opportunistic pathogen is one that is particularly like to cause disease in what type of host? Multiple choice question. non-human animals vaccinated immunocompromised homosexual men
immunocompromised
The time period between when a pathogen enters a host and the development of symptoms is called the __________ period and it will vary from disease to disease.
incubation
The time period between when a pathogen enters a host and the development of symptoms is called the ______________ period and it will vary from disease to disease.
incubation
When a pathogen is growing and multiplying within or on a host (which may or may not result in overt symptoms) this is known as a(n) ______. Multiple choice question. infectious disease infection latent infection opportunistic infection
infection
When a pathogen is growing and multiplying within or on a host (which may or may not result in overt symptoms) this is known as a(n) ______. Multiple choice question. opportunistic infection infectious disease infection latent infection
infection
When the presence of a pathogen or its products results in the impairment or loss of function of a host system, this is a(n) ______. Multiple choice question. infectious disease opportunistic infection latent infection infection
infectious disease
When the presence of a pathogen or its products results in the impairment or loss of function of a host system, this is a(n) ______. Multiple choice question. latent infection infection opportunistic infection infectious disease
infectious disease
Microbial pathogens that are able to grow and replicate within a host cell are typically called __________ pathogens.
intracellular
Select all that apply Select two symptoms (as opposed to signs) of an infectious disease. Multiple select question. fever loss of appetite blood in the stool pain rash
loss of appetite pain
An organism that infects a host when it gets out of its typical niche (normal location in the body) is a(n) ______. Multiple choice question. microorganism virulent pathogen parasite opportunistic pathogen
opportunistic pathogen
Select the best term for a large segment (10-200 kilobases) of bacterial chromosomal and plasmid DNA that encodes virulence factors. Multiple choice question. endogenous retrovirus provirus pathogenicity island virulence allele
pathogenicity island
N. gonorrhoeae
phase variation of pili proteins; also produces proteases
Select three types of adherence structures used by infectious agents for attachment. Multiple select question. pili and fimbriae specialized adhesion molecules (e.g. viral glycoproteins) inclusion bodies (e.g. carboxysomes) capsules exotoxins
pili and fimbriae specialized adhesion molecules (e.g. viral glycoproteins) capsules
A body surface where infectious agents may gain access to host tissue is called a ____________ of entry.
portal
In relation to infectious diseases, the skin, respiratory system, gastrointestinal tract, urogenital system, and conjunctiva of the eye are all examples of ______. Multiple choice question. areas that are immune to disease manifestation by virtue of their anatomy areas possessing a significantly higher degree of immune response than the rest of the body, preventing infections portals of entry through which infectious agents may gain access to host tissues
portals of entry through which infectious agents may gain access to host tissues
One mechanism used by some bacteria to evade specific immune responses (e.g. antibodies) is to ______. Multiple choice question. invade and remain resident within plasma cells, where secreted antibodies can't bind to them produce toxins that selectively destroy antibody-producing plasma cells produce capsules that resemble host tissue components, acting as a disguise of sorts produce receptors that bind the Fab portion of antibody molecules
produce capsules that resemble host tissue components, acting as a disguise of sorts
One mechanism used by some bacteria to evade specific immune responses (e.g. antibodies) is to ______. Multiple choice question. produce toxins that selectively destroy antibody-producing plasma cells produce capsules that resemble host tissue components, acting as a disguise of sorts invade and remain resident within plasma cells, where secreted antibodies can't bind to them produce receptors that bind the Fab portion of antibody molecules
produce capsules that resemble host tissue components, acting as a disguise of sorts
S. pyogenes
produces a capsule that resembles host tissue components; also produces protein G
N. gonnorrhoeae
produces proteases that digest host proteins such as IgA
In an AB exotoxin molecule, the A portion ______. Multiple choice question. fails to stimulate any immune response by the host binds to the target receptor on a host cell is a component of the bacterial cell wall produces the negative effect of the toxin inside the cell
produces the negative effect of the toxin inside the cell
A low ID50 value means ______. Multiple choice question. relatively small numbers of microorganisms are required to kill an infected organism relatively small numbers of microorganisms are required to establish an infection relatively large numbers of microorganisms are required to kill an infected organism relatively large numbers of microorganisms are required to establish an infection
relatively small numbers of microorganisms are required to establish an infection
What type of shock can result from exposure to relatively large amounts of the lipid A component of Gram-negative bacteria, and the subsequent release of large amounts of cytokines like IL-1 and tumor necrosis factor? Multiple choice question. psychogenic shock septic shock neurogenic shock anaphylactic shock
septic shock
What type of shock can result from exposure to relatively large amounts of the lipid A component of Gram-negative bacteria, and the subsequent release of large amounts of cytokines like IL-1 and tumor necrosis factor? Multiple choice question. septic shock psychogenic shock neurogenic shock anaphylactic shock
septic shock
In the context of infectious diseases, objective changes in the body that can be directly observed or measured (such as fever) are called _______________.
signs
Which type of bacterial exotoxin stimulates a large proportion of the host T cell population to produce excessive amounts of cytokines? Multiple choice question. diphtheria toxin lipopolysaccharide AB toxin superantigen
superantigen
The human immunodeficiency virus (HIV) is an example of a pathogen that has evolved to ______ the host's immune response. Multiple choice question. avoid mimic duplicate suppress
suppress
Select all examples of common vehicles that could be referred to as fomites. Multiple select question. cats surgical instruments arthropods bedding drinking vessels
surgical instruments bedding drinking vessels
____________ of an infectious disease are subjective changes experienced by the patient, such as pain and loss of appetite.
symptoms
_________________ of an infectious disease are subjective changes experienced by the patient, such as pain and loss of appetite.
symptoms
A disease __________ is a set of signs and symptoms that are characteristic of the disease.
syndrome
The best definition of the incubation period of an infectious disease is when ______. Multiple choice question. the pathogen has entered the host and is multiplying, but hasn't reached high enough levels to cause clinical manifestations there is an onset of signs and symptoms, but they are not yet specific enough for disease diagnosis the disease is most severe, and the patient displays characteristic signs and symptoms signs and symptoms of the illness begin to disappear, and the patient recovers
the pathogen has entered the host and is multiplying, but hasn't reached high enough levels to cause clinical manifestations
Large segments of bacterial chromosomal and plasmid DNA encoding virulence factors are known as pathogenicity "islands" because ______. Multiple choice question. they are broken into pieces and inserted as fragments into existing DNA they exist separately from chromosomal RNA they appear to have been inserted intact into existing DNA they exist separately from chromosomal DNA
they appear to have been inserted intact into existing DNA
Which term describes the ability of a microorganism to produce substances that alter host cell metabolism in a negative way? Multiple choice question. toxin intoxication toxigenicity toxemia
toxigenicity
Which term refers to a substance that alters the normal metabolism of host cells with negative effects on the host organism? Multiple choice question. toxemia toxigenicity intoxication toxin
toxin
Which is an example of vertical transmission of a pathogen? Multiple choice question. Lyme disease contracted through a bite from a tick transmission of a German measles virus across the placenta to a developing fetus transmission of hepatitis B virus via IV drug use with a contaminated shared needle respiratory tract droplets sneezed from a person with influenza viruses breathed in by another individual
transmission of a German measles virus across the placenta to a developing fetus
When a microorganism is restricted to infecting only a particular cell or tissue type, this is known as a(n) _____________.
tropism
A(n) ______________ is an organism that facilitates the spread of disease from one host to another. Examples include mosquitoes, ticks, and fleas.
vector
Direct living transmitters of a pathogen, such as arthropods, are called ___________.
vectors
An organism's ______ is the degree of harm (pathogenicity) inflicted on its host. Multiple choice question. mortality morbidity infectivity virulence
virulence
Because their expression is associated with the production of disease in their host, bacterial toxins, superantigens, and attachment factors are all be considered to be ____________ factors.
virulence
The ability of an organism (usually a microbe) to cause disease is its ______________.
virulence
The degree of harm (pathogenicity) inflicted on the host is best defined as a pathogen's __________.
virulence
Which of the following is a general class of molecules that enables a microorganism to cause host cell or tissue damage? Multiple choice question. botulism toxin inclusion bodies virulence factors plasmids
virulence factors
Multiple Select Question Select all that apply Select three typical systemic effects of lipid A on host organisms Multiple select question. weakness constipation shock fever antiinflammatory effects
weakness shock fever
An infectious disease that is transmitted from an animal to a human is termed a(n) ______. Multiple choice question. opportunistic infection vector-borne infection vertically-transmitted infection zoonosis
zoonosis
Staphylococcus
Choice, produces protein A to interfere with immune system recognition produces protein A to interfere with immune system recognition
____ contact transmission typically results from an actual physical interaction with the infectious source (e.g. person to person contact). ______ contact transmission depends upon something acting to "transfer" the infectious agent between hosts. Multiple choice question. Direct; Indirect Indirect; Direct Airborne; Vertical Vertical; Horizontal
Direct; Indirect
True or false: A disease syndrome is one defining symptom of a particular disease. True false question. True False
False
True or false: Bacterial endotoxins produced by different species have very distinct structures and produce variable effects on different target cells. True false question.TrueFalse
False
Select the best example of indirect contact transmission. Multiple choice question. transmission of Epstein-Barr virus, the cause of "mono," by kissing Lyme disease contracted through a bite from a tick HIV infection via IV drug use with a contaminated shared needle genital herpes transmission during sexual intercourse
HIV infection via IV drug use with a contaminated shared needle
Human immunodeficiency virus (HIV)
Infect cells of the immune system and diminish their function
Select the best description of vector-borne transmission. Multiple choice question. acquisition of HIV infection via IV drug use with a contaminated shared needle transmission of Toxoplasma parasites across the placenta to a developing fetus Lyme disease contracted through a bite from a tick transmission of the common cold virus via a contaminated drinking glass
Lyme disease contracted through a bite from a tick
Neisseria gonorrhoaea
Produce modified lipooligosaccharides on their surface to interfere with host mechanisms that would otherwise lyse them
Streptococcus pneumoniae, Neisseria meningitidis, Haemophilus influenzae
Produce slippery mucoid capsule that prevents host immune cells from effectively capturing them
H. influenzae
Produces a capsule that prevents deposition of host complement
What does it mean to say a microbe has a specific tropism? Multiple choice question. The ability of the microbe to bind to any host cells or tissues, regardless of what receptors are present. A requirement for successful competition against normal host microbiota for nutrients. The microbe infects only specific cell or tissue types as dictated by the correct receptor being present on them.
The microbe infects only specific cell or tissue types as dictated by the correct receptor being present on them.
Select the definition of infectious dose 50 (ID50). Multiple choice question. The amount of antibiotic required to eliminate an infectious disease in at least 50% of the infected population. The number of microbes required to induce disease in 50% of the inoculated hosts. The number of microbes required to kill 50% of inoculated host organisms. The number of microbes required to induce disease in an individual over 50 years of age.
The number of microbes required to induce disease in 50% of the inoculated hosts.
Select the definition of infectious dose 50 (ID50). Multiple choice question. The number of microbes required to induce disease in an individual over 50 years of age. The number of microbes required to induce disease in 50% of the inoculated hosts. The amount of antibiotic required to eliminate an infectious disease in at least 50% of the infected population. The number of microbes required to kill 50% of inoculated host organisms.
The number of microbes required to induce disease in 50% of the inoculated hosts.
Select the best definition of lethal dose 50 (LD50). Multiple choice question. The number of microbes required to kill 50% of inoculated host organisms. The number of microbes that will infect an individual 50% of the time. The amount of antibiotic required to eliminate an infectious disease in at least 50% of the infected population. The number of microbes required to induce clinical disease in 50% of the inoculated hosts.
The number of microbes required to kill 50% of inoculated host organisms.
What do these infectious diseases have in common: Lyme disease, malaria, plague, Rocky Mountain Spotted fever, and West Nile virus? Multiple choice question. They are all caused by viruses. They are all transmitted by arthropod vectors. They are all considered sexually transmitted diseases. None of them occurs in the United States.
They are all transmitted by arthropod vectors.
A good example of transmission of a zoonosis is ______. Multiple choice question. human to human transmission of measles a human contracting rabies from a raccoon bite a human contracting botulism from eating spoiled food human hepatitis A resulting from drinking contaminated water
a human contracting rabies from a raccoon bite
A high LD50 value means ______. Multiple choice question. a relatively small number of microorganisms is required to induce an infection a relatively large number of microorganisms is required to induce an infection. a relatively small number of microorganisms is required to kill an infected organism a relatively large number of microorganisms is required to kill an infected organism
a relatively large number of microorganisms is required to kill an infected organism
The image illustrates different microbial molecules that are specifically involved in ______. Multiple choice question. motility adherence killing host cells evading the immune response
adherence
In _____________________ transmission, a pathogen is often sneezed or coughed into the air and suspended in dust, droplet nuclei, or larger respiratory droplets.
airborne
