WorksheetsExam 2
Total questions: 100
Worksheet time: 50mins
Which of the following statements about helminths is FALSE?
They have eukaryotic cells.
They are multicellular animals.
Some have male and female reproductive organs in one animal.
They are heterotrophic.
All are parasites.
Most helminthic diseases are transmitted to humans by ____.
genitourinary route
vectors
respiratory route
gastrointestinal route
aerosols
The encysted larva of the beef tapeworm is called a ____.
proglottid
cercaria
metacercaria
cysticercus
redia
The definitive host of a parasite is ____.
also the vector for the parasite
the host for immature stages of the parasite
where the mature form of the parasite occurs
the host for the dormant stage of the parasite
the host that the parasite name is based on
Which of the following pairs is mismatched?
nematodes — complete digestive tract
nematodes — many are free-living
trematodes — flukes
cestodes — all are free-living
cestodes — segmented body made of proglottids
Which of the following statements provides the most significant support for the idea that viruses are nonliving chemicals?
They are not composed of cells.
They cannot reproduce themselves outside a host.
They are filterable.
They cause diseases similar to those caused by chemicals.
They are chemically simple
Three weeks after a river rafting trip, three family members experienced symptoms of coughing, fever, and chest pain. During the rafting trip, the family had consumed crayfish that they caught along the river banks. An examination of the patients' sputum revealed helminth eggs, and serum samples were positive for antibodies to Paragonimus. All of the family members recovered following treatment with praziquantel. In the Paragonimus life cycle, ____.
the source of the infection was the river water
both humans and crayfish are intermediate hosts
the crayfish are the definitive host and humans are the intermediate host
humans are the definitive host and crayfish are the intermediate host
both humans and crayfish are definitive hosts
A person reports to a clinic complaining of fever and abdominal pain. The abdomen is swollen, and blood tests indicate liver damage. A stool sample is examined under a microscope and found to contain eggs with a spine projecting from its surface. The indications are consistent with infection with ____.
Echinococcus granulosus
Taenia solium
Ancylostoma duodenale
Enterobius vermicularis
Schistosoma mansoni
Which of the following nematodes can be transmitted by mosquitoes?
Enterobius vermicularis
Ascaris lumbricoides
Ancylostoma duodenale
Wuchereria bancrofti
Necator americanus
Which of the following is a characteristic by which viruses are classified?
Type of host
Number of chromosomes
Type of life cycle
Type of nucleic acid
Size
Public health scientists discover and become concerned about a new strain of RNA virus among farm animals, especially geese and pigs, in the Midwest. Each virion is composed of lipid, helical proteins, and multiple pieces of RNA. This new virus may be a(n) ____.
dengue virus
coronavirus
rotavirus
hantavirus
influenza virus
Which of the following statements about viral spikes is FALSE?
They bind to receptors on the host cell surface.
They are composed of carbohydrate-protein complexes.
They are found only on nonenveloped viruses.
They may cause hemagglutination.
They are used for attachment.
An envelope is acquired during which of the following steps?
Adsorption
Release
Penetration
Uncoating
Biosynthesis
How are prions different from all other known infectious agents?
They cannot reproduce outside a cell.
They cause neurological problems.
They can be destroyed by incineration.
They act as slow viruses.
They lack nucleic acid.
Reverse transcriptase is associated with which of the following?
retroviruses
dsRNA viruses
-ssRNA viruses
+ssRNA viruses
dsDNA viruses
A homeschooled child recently visited an ailing great-grandparent who was complaining of a painful rash. Even though the child had had no contact with children suffering from chickenpox, the child developed chickenpox. How did the child contract the infection?
The virus was likely contracted from fomites.
The adult had shingles and the child was exposed to virus particles.
There is insufficient information for a conclusion.
The adult had chickenpox and exposed the child.
An insect vector infected the child.
A lytic virus has infected a patient. Which of the following would best describe what is happening inside the patient?
The virus is infecting cells and then releasing only small amounts of virus.
The virus is not killing any cells in the host.
The virus is incorporating its nucleic acid with that of the patient's cells.
The virus is slowly killing the patient's cells.
The virus is causing the death of the infected cells in the patient.
A virus's ability to infect an animal cell depends primarily upon the ____.
enzymatic activity of a host cell
type of viral nucleic acid
presence of receptor sites on the cell membrane
host cell's ability to phagocytize viral particles
presence of pili on the host cell wall
Which of the following places these items in the correct order for DNA-virus replication?
1. Maturation
2. DNA synthesis
3. Transcription
4. Translation
2; 3; 4; 1
1; 2; 3; 4
4; 1; 2; 3
3; 4; 1; 2
4; 3; 2; 1
Characteristic features of the herpesvirus used for diagnosis include the ____.
presence of recurring lesions in the lip or genital regions and syncytia in infected tissue
presence of syncytia in infected tissue
presence of viruses intracellularly years after recovery from the infection
ability of the virus to be transmitted to neonates
presence of recurring lesions in the lip or genital regions
The fungus Pneumocystis jiroveci is found in the lungs of most people in low numbers, but in immunocompromised people it overgrows, resulting in severe respiratory problems. The fungus is best described as ____.
a mutualist symbiotic partner
both resident microbiota and opportunistic pathogen
a parasite
resident microbiota
transient microbiota
Symptoms are ____.
objective manifestations of a disease that can be measured
characteristics of a disease, such as sweating
laboratory tests used to diagnose a disease
objective manifestations of a disease that can be observed by others
subjective characteristics of a disease that only the patient can feel
Which of the following statements regarding the demonstration of the etiology of disease is FALSE?
It must be possible to reisolate the suspect agent from the infected experimental host.
The suspect agent must be isolated and cultured in the laboratory.
The suspect agent must cause the disease under investigation when introduced into a susceptible host organism.
The suspect agent must be the only potential pathogen present in disease cases.
The suspect agent must be present in all cases of disease.
A person is exposed to rotten wood with fungal growth and develops blastomycosis. No one taking care of him/her becomes ill. Blastomycosis is an example of a ________ disease.
chronic
subacute
noncommunicable
latent
contagious
Which of the following situations is NOT a way in which a baby acquires normal microbiota?
The baby acquires the residential microbiota in the colon after the first meal.
Microbes enter the nose and mouth when the baby is in the birth canal.
Microbes cross the placenta during pregnancy.
Microorganisms grow in the respiratory tract after the baby's first breath.
Staphylococcus epidermidis is transferred from the hospital staff to the newborn after delivery.
Which of the following is transmitted by the parenteral route?
Gonorrhea
Yellow fever
Ringworm
Pertussis
Warts
Which of the following is considered a mechanical vector transmission?
Flea transmission of Yersinia
Louse transmission of Rickettsia
Mosquito transmission of Plasmodium
Tsetse fly transmission of Trypanosoma
Cockroach transmission of Shigella
Which of the following is a sign of disease?
Headache
Cramps
Dizziness
Fever
Nausea
The bacterium that causes tuberculosis can be expelled from the lungs by a cough and remain viable in the air for an hour or more. If a person inhales the bacteria from the air, what type of transmission has occurred?
Bodily fluid
Indirect contact
Waterborne
Foodborne
Airborne
Which of the following is an example of vehicle transmission of disease?
Malaria acquired through the bite of a mosquito.
Salmonellosis acquired through ingestion of contaminated food.
Lyme disease acquired from a tick infestation.
Gonorrhea acquired through sexual intercourse with an infected person.
A cold acquired through inhalation of respiratory droplets.
In early spring 2009, the CDC reported several dozen cases of novel H1N1 influenza ("swine flu") in the United States. By the summer, the number of confirmed cases was reported as over 40,000. The pattern of novel H1N1 cases in the United States represents a(n) ____ disease.
opportunistic
epidemic
endemic
pandemic
sporadic
People who wash their hands frequently during cold season typically have fewer colds than those who do not. This observation suggests cold viruses can be transmitted by ____.
both direct contact and fomites
fomites
direct contact
mechanical vectors
biological vectors
Organisms that are resident microbiota are best described as ____.
microorganisms that remain with the person throughout life
microorganisms that never cause disease
any microorganisms that cause disease
microorganisms that may cause a disease under certain circumstances
organisms that remain in the body for a short time
A reservoir is ____.
a source of microbes for laboratory testing
a source of microbial contamination
an environment that is free of microbes
a condition in which organisms remain in the body for a short time
any microorganism that causes disease
The degree to which an organism is able to cause disease is referred to as its ____.
seriousness
pathogenicity
acuteness
chronicity
communicability
Pneumocystis pneumonia in an AIDS patient would be considered a ____.
genetic disease
communicable disease
local infection
secondary infection
primary infection
The incidence of tuberculosis in the year 2000 in the United States was 12.43/100,000 cases. This means ____.
there were 12.43 new cases of tuberculosis for every 100,000 people in the United States in the year 2000
there were 12.43 tubercle bacilli per 100,000 microbes in the United States in the year 2000
12.43 of every 100,000 people in the United States had tuberculosis in the year 2000
12.43 of every 100,000 people died of tuberculosis in the United States in the year 2000
12.43 of every 100,000 cases of tuberculosis were treated in the United States in the year 2000
Invasiveness refers to the ability of a parasite to ____.
add to its virulence by transduction
enter through a variety of portals of entry
penetrate tissues and spread
digest different host tissues
convert toxins to toxoids
If a pathogen is part of a biofilm, its virulence is enhanced because ____.
it is more invasive
it can produce more toxins
it is more resistant to osmotic changes
it is protected from phagocytes and drugs
its infectious dose is decreased
Fomites are ____.
insects that transmit pathogens from an infected host to a noninfected host
inanimate objects involved in the indirect contact transmission of pathogens
animal sources for human pathogens
fecal material from infected hosts
silent carriers of infectious diseases
From which of the following body sites would you expect to isolate Staphylococcus, Propionibacterium, Streptococcus, and Corynebacterium as the primary colonizing microbiota?
Small intestine
Skin
Stomach
Deep gum regions
Liver
Recent research has demonstrated a correlation between the presence of certain types of Gram-positive bacteria in the human gut with obesity and type 2 diabetes. These findings best support which of the following statements?
Gram-positive bacteria compose the majority of normal microbiota in the human gut of people with obesity and type 2 diabetes.
Normal microbiota may significantly impact human health and disease.
Obesity and type 2 diabetes is caused by normal microbiota in the human gut.
The presence of Gram-positive bacteria in the human gut causes obesity and type 2 diabetes.
Normal microbiota does not at all affect human health and disease.
An organism that is able to be transmitted from one host to another is said to be ____.
pathogenic
infective
rudimentary
communicable
virulent
When would Koch's postulates be utilized?
Determination of the cause of a new disease in a microbiology research lab
Development of a new antibiotic in a pharmaceutical lab
Determination of the cause of a patient's illness in a hospital microbiology lab
Formulation of a vaccine against a new pathogen in a genetic engineering lab
Whenever the scientific method cannot be used to investigate a microbiological problem
A teacher walking through her first-grade classroom pauses to pick up a used tissue that had ended up on the floor instead of in the waste basket. Unfortunately, after discarding the tissue, she doesn’t immediately wash her hands, and acquires a strain of rhinovirus. Several days later she begins to experience symptoms of a cold. Based upon this scenario, please select the mode of disease transmission demonstrated here.
Vector
Direct contact (touching)
Fomite
Air
Droplet
In which of the following situations did disease develop due to vertical transmission of the pathogen?
A traveler develops COVID-19 after sharing a buffet with 900+ other individuals on a cruise ship.
A fetus develops listeriosis after unpasteurized cheese infected with Listeria bacteria is consumed by the mother during pregnancy.
A mother accidentally sneezes into a bowl of ice cream before giving this bowl to her daughter.
A dog develops rabies after being scratched during a fight with a raccoon that carries the virus.
A hospitalized patient develops MRSA (Methicillin-resistant Staphylococcus aureus) bacteria in a wound following surgery.
When a pathogen is transferred from a water source to an animal before being transferred to a human, the animal is called a(n) ____ agent.
intermediate
ectoparasitic
reservoir
endoparasitic
transfer
All of the following situations are passive modes of penetration for the invasion of host tissues by opportunistic pathogens EXCEPT ____.
a firefighter receiving third-degree burns on the skin
a teenager getting diarrhea from eating food infested by fungi
a bacterium adhering to intravenous tubing, forming a biofilm
a hiker being bitten by a tick
a child falling and scraping her knee
Which statement regarding the skin microbiome is correct?
Sites rich in sebaceous glands have the greatest diversity of bacteria.
The dry sites of the skin exhibit a lack of microbial diversity compared to other sites.
Dry areas, such as the forearms and buttocks, host the greatest diversity of bacteria.
The skin microbiome is uniform, regardless of localized pH, salt content or moisture.
Helminthic parasites are the most common group of organisms on the skin.
Precautions that can be taken by individuals to prevent travel-related infectious diseases include ____.
get or update vaccinations appropriate for specific destinations
take antibiotics prophylactically for potential bacterial infections
wash hands with soap and water frequently
wash hands with soap and water frequently, get or update vaccinations appropriate for specific destinations, and take antibiotics prophylactically for potential bacterial infections
wash hands with soap and water frequently and get or update vaccinations appropriate for specific destinations
Which of the following types of experimental evidence suggests that a particular organism thought to be part of the human microbiome is, in fact, just a laboratory contaminant?
Absence of ribosomal RNA evidence in a specific host location where the organism was believed to have colonized.
Presence of ribosomal RNA evidence in a specific host location where the organism was believed to have colonized.
Presence of ribosomal RNA evidence in a specific host location where the organism was not expected to have colonized.
Absence of ribosomal RNA evidence in a specific host location where the organism was not expected to have colonized.
Absence of any ribosomal RNA of the organism in question at any host location.
One example of infectious disease transmission by a fomite is ____.
a child developing a cold after playing with a toy that harbored rhinovirus
two college students (both 21 years old) having unprotected sex
a baby born with congenital syphilis from an infected mother
a teenager with severe acne due to propionibacteria growing in sebaceous glands D)
a camper drinking water directly out of a creek
Consider the links in the chain of infection. Which of the links is broken when hands are thoroughly washed?
The agent
Virulence
Susceptibility
Exposure
Dose
A(n) _____ is an increase in disease occurrence within a large population over a very wide region (usually the world).
pandemic
sporadic disease
endemic
outbreak
epidemic
A(n) ______ rate measures the number of individuals who become ill as a result of a specific disease within a susceptible population during a specific time period.
prevalence
morbidity
incidental
mortality
index
A(n) _______ epidemic is characterized by a sharp rise to a peak then a rapid, but not as pronounced, decline in the number of individuals infected.
common source
herd
propagated
inductive
sporadic
Increasing global population, overcrowding, and international travel have contributed to many changes in epidemiological trends of infectious disease. Which of the following would have been just as likely to occur a century ago as today?
Gonorrhea, one of the oldest known STDs, is becoming increasingly difficult to treat due to multi-drug resistance strains of Neisseria gonorrhea.
Measles has been completely eradicated and is no longer a threat.
The incidence of bubonic plague in humans, transmitted via the rat flea, is gradually increasing in the United States with most of the cases reported in the west.
An individual was placed under a government-ordered isolation after traveling while infected with a drug-resistant strain of Mycobacterium tuberculosis.
West Nile encephalitis, a zoonotic disease caused by a virus first isolated in Uganda, is now a world-wide pandemic in humans and animals.
Over the past 100 years, the number of deaths due to infectious disease has ____ while the deaths due to metabolic diseases have ____.
increased; decreased
increased; remained the same
decreased; remained the same
remained the same; increased
decreased; increased
Eight 10-year-olds in the community became sick within a 24-hour period with vomiting and diarrhea. Personnel from the health department interviewed the children and their families, attempting to determine the source of the illness. Which piece of information below is most suggestive of the common source?
All eight children attended the same birthday party two days prior to becoming ill.
All eight children go to the same school.
Six of the eight children are on the same soccer team, which practices three times/week.
In two of the eight families, siblings were just beginning to show signs of illness at the time of the interview.
Five of the eight children ride the same school bus.
Which of the following is an example of a noncommunicable infectious disease?
Strep throat
Urinary tract infection
COVID-19
Diabetes mellitus
Influenza
Innate immunity _____.
utilizes highly specific antigen receptors on B cells
is found only in vertebrate animals
is based on recognition of antigens that are specific to different pathogens
is activated immediately upon infection
depends on an infected animal's previous exposure to the same pathogen
Engulfing-phagocytic cells of innate immunity of vertebrates include _____.
I) neutrophils
II) macrophages
III) dendritic cells
IV) natural killer cells
I and IV
I II and III
II and IV
I and III
I, II, III, and IV
Inflammatory responses typically include _____.
inhibiting the release of white blood cells from bone marrow
increased activity of phagocytes in an inflamed area
reduced permeability of blood vessels to conserve plasma
release of substances to decrease the blood supply to an inflamed area
clotting proteins migrating away from the site of infection
A boy falls while riding his bike. A scrape on his hand almost immediately begins to bleed and becomes red, warm, and swollen. What response is occurring?
lytic response
autoimmune response
lysosomal response
inflammatory response
adaptive immune response
Phagocytosis of microbes by macrophages is enhanced by _____.
I) the binding of antibodies to the surface of microbes
II) antibody-mediated agglutination of microbes
III) the release of cytokines by activated B cells
only II and III
only II and III
only II
I, II, and, III
only I and II
Approximately one month upon returning from a river rafting trip in South America, a college student develops a fever accompanied by chills, muscle aches, and abdominal discomfort. After being examined by physicians at the university health center, the student is referred to an infectious disease specialist, where a diagnosis of schistosomiasis is made. Schistosoma is a helminth that contaminates freshwater in areas that lack proper sanitation, and often leads to infection when the water is used for swimming or bathing. In this case, bloodwork from the student would most likely reveal an elevation in which of the following cells?
Erythrocytes
Basophils
Platelets
Eosinophils
T helper cells
Complement _________.
results in lysis of Gram-positive bacteria
augments opsonization of bacteria by antibodies
results in lysis of Gram-negative bacteria
both augments opsonization of bacteria by antibodies and results in lysis of Gram-negative bacteria
All of the choices are correct.
In which of the following areas of the human body do secretions play the greatest role in preventing microbial colonization?
Genital tract
Large intestine
Large intestine
Skin
Stomach
Adaptive immunity is based upon _____.
plants being exposed to new pathogens
traits common to groups of pathogens
pathogen-specific recognition
maternal provision of antibodies to offspring
having exhausted all options for innate immunity responses
Antigens are _____.
proteins that consist of two light and two heavy polypeptide chains
foreign molecules that trigger an immune response
proteins embedded in B cell membranes
proteins released during an inflammatory response
proteins found in the blood that cause foreign blood cells to clump
An epitope associates with which part of an antibody?
the tail
the heavy-chain constant regions only
the light-chain constant regions only
the disulfide bridge
variable regions of a heavy chain and light chain combined
B cells interacting with helper T cells are stimulated to differentiate when _____.
helper T cells differentiate into cytotoxic T cells
B cells release cytokines
B cells produce IgE antibodies
helper T cells release cytokines
cytotoxic T cells present the class II MHC molecule-antigen complex on their surface
Antibodies of the different classes IgM, IgG, IgA, IgD, and IgE differ from each other _____.
in their interaction with phagocytes
in the way they are produced
in the type of cell that produces them
in their heavy-chain structure
by the antigenic determinants that they recognize
The major histocompatibility (MHC) molecule is important in a T cell's ability to _____.
identify specific bacterial pathogens
recognize specific parasitic pathogens
recognize differences among types of cancer
identify specific viruses
distinguish self from nonself
Which of the following is NOT an effect of the complement components C3a and C5a binding their receptors on leukocytes?
Increased vascular permeability via induction of TNF-α and IL-6 secretion
Induction of degranulation by granulocytes
None of the above is an effect of C3a and C5a binding their receptors.
All of the above are effects of C3a and C5a binding their receptors.
Increased smooth muscle contraction to aid in delivering immune cells and molecules to the site of infection
A newborn who is accidentally given a drug that destroys the thymus would most likely _____.
lack innate immunity
be unable to genetically rearrange antigen receptors
be unable to differentiate and mature T cells
lack class I major histocompatability (MHC) molecules on cell surfaces
have a reduced number of B cells and be unable to form antibodies
Arrange in the correct sequence these components of the mammalian immune system as it first responds to a pathogen.
I) Pathogen is destroyed.
II) Lymphocytes secrete antibodies.
III) Antigenic determinants from pathogen bind to antigen receptors on lymphocytes.
IV) Lymphocytes specific to antigenic determinants from pathogen become numerous.
V) Only memory cells remain.
III → II → I → V → IV
II → I → IV → III → V
I → III → II → IV → V
IV → II → III → I → V
III → IV → II → I → V
Which of the following statements are fundamental to the clonal-selection theory of how the adaptive immune system functions?
I) Each lymphocyte has a unique membrane receptor that recognizes one antigen.
II) When the lymphocyte binds an antigen, it is activated and begins dividing to form many identical copies of itself.
III) Cloned lymphocytes have slight differences and are selected by the spleen for removal if they do not bind an antigen.
IV) Cloned cells descend from an activated lymphocyte and persist even after the pathogen is eliminated.
only II, III, and IV
only I, II, and IV
only I and III
only II and IV
I, II, III, and IV
Select the pathway that would lead to the activation of cytotoxic T cells.
self-tolerance of immune cells → B cells contact antigen → cytokines released
body cell becomes infected with a virus → new viral proteins appear → class I MHC molecule-antigen complex displayed on cell surface
cytotoxic T cells → class II MHC molecule-antigen complex displayed → cytokines released → cell lysis
complement is secreted → B cell contacts antigen → helper T cell activated → cytokines released
B cell contact antigen → helper T cell is activated → clonal selection occurs
Infection with HIV (human immunodeficiency virus) typically _____.
is found in B cells but not in T cells
leads to an immediate decrease in the number of HIV in the blood
increases the level of helper T cells for the first year after infection
eliminates all T cells immediately
alters mitochondrial but not genomic DNA sequences
Vertical transmission occurs from:
prions to animal.
mother to fetus.
virus to animal.
animal to human.
prokaryote to eukaryote.
Which of the following diseases is not the result of direct contact transmission?
AIDS
Common cold
Oral herpes
Gonorrhea
Cholera
ID50 describes
the number of cells or virions needed to establish an infection in 50 percent of exposed hosts.
the amount of toxin lethal to a 50-pound human or other animal.
the number of cells or virions which will kill 50 individuals.
the number of cells or virions which will kill 50% of exposed hosts.
the percentage of individuals which will develop an infection after exposure to 50 cells or virions.
Invasiveness refers to the ability of a parasite to:
convert toxins to toxoids.
add to its virulence by transduction.
cause at least three signs of disease.
penetrate tissues and spread.
enter through a variety of portals of entry.
Pathogenicity islands refer to:
ecosystems where a high diversity of host-pathogen interactions can be found.
clusters of genes responsible for virulence.
pathogens in biofilm aggregations.
areas of the body prone to infection.
areas within a reservoir where pathogens can be found
Such factors as the number of organisms, their generation time and virulence, and the level of host resistance can influence:
the incubation period for a disease.
how the body is entered.
the activation rate of leukocytes.
whether or not an organism produces exotoxins.
hemolysin and leukocidin production.
Tetanus will not occur in the tissue of the small intestine because:
the body's white blood cells are particularly active.
the organisms will grow, but do not produce toxins in this area.
the organisms in the small intestine will inhibit the growth of the tetanus-producing bacterium.
the portal of entry for tetanus spores is parenteral.
lymph does not flow through the intestine.
Hyaluronidase is a bacterial enzyme that:
destroys blood clots in the host.
digests peptidoglycan cell walls of bacteria.
enhances penetration of a pathogen through the host tissues.
encourages movement in the organism.
induces blood clot formation in the host.
Which of the following does not apply to endotoxins?
They are composed exclusively of protein.
They are present in gram-negative bacteria.
They do not stimulate an immune response that leads to the production of antibodies.
They are part of the bacterial cell wall.
They are a product of the lipopolysaccharide (LPS) complex.
Yearly vaccination of humans for influenza viruses is necessary because _____.
of an increase in immunodeficiency diseases
surviving the flu one year exhausts the immune system to non-responsiveness the second year
rapid mutation in flu viruses alters the surface proteins in infected host cells
the flu can generate anaphylactic shock
flu leads to autoimmune disorders
The degree or extent of disease that a pathogen causes is
attenuation
toxicity
a host factor.
virulence
pathogenicity
An attenuated pathogen
is part of the normal human microbiome.
has recently acquired virulence factors allowing it to jump species.
has become antibiotic-resistant.
produces toxins.
has lost virulence factors needed to cause disease in an immune competent host.
Which statement shows an example of a commensal species in one host becoming a pathogenic species in another host?
Shigella flexneri preferably infects the tissues of humans and other primates.
Up to 30% of pregnant women harbor Group B streptococci in the vagina to no ill effect, but when transmitted to their newborns, a proportion of babies develop serious infection.
New infectious diseases are due to increases in host tropism.
Clostridium difficile flourishes in the large intestine after antibiotic therapy.
Escherichia coli lives harmlessly in the appendix but will be attacked by the immune system if ii invades the abdominal cavity.
Toxemia is a condition
where a vaccine is used to protect against a toxin.
where a toxin has entered the bloodstream resulting in systemic effects.
that may describe both localized and systemic effects.
where a toxin acts as a superantigen.
where a toxin is acting on tissues locally.
A potential antimicrobial drug is tested and found to strip away the capsules made by certain pathogenic bacteria. How would this drug affect the bacteria's ability to cause disease?
The bacteria would only be able to colonize surface tissues and not penetrate more deeply.
The phagocytes would be better able to ingest the bacteria.
The bacteria would not be able to kill phagocytes.
The bacteria would be unable to survive inside the phagocyte.
The bacteria would be unable to acquire needed nutrients from the body.
Pathogens can obtain iron from the body using
transferrin
proteases
insulin
lipases
siderophores
Which of the following is not a way that pathogens can avoid destruction by the phagocytes of the host immune system?
Neutralize the hydrolytic enzymes produced by the phagocyte
Adapt to living inside the phagocyte
Release toxins which kill the phagocyte
Block fusion of the phagosome with the lysosome inside the phagocyte
Make a capsule which is toxic to the phagocyte
How are symptoms of an infection associated with the mode of transmission of the pathogen?
The worse the patient feels, the more likely the disease is transmissible to others.
Lack of symptoms indicates that the infection is not transmissible to others.
Bodily fluids are rarely a source of disease transmission during an infection.
There is no relationship between symptoms and mode of transmission.
Bodily fluids produced during an illness are often rich in infectious organisms.
Which of the following is not a way that bacteria can evade complement activation?
Produce proteins that mimic our naturally occurring regulators of complement activation
Release enzymes that break down antibodies that trigger complement activation
Release enzymes that break down complement proteins
Build a capsule to hide surface antigens that would trigger complement activation
Release enzymes that break down lectins responsible for triggering complement activation
Which of the following is not a main goal of inflammation?
Limit the spread of infectious agents
Produce localized heat and swelling in an effort to denature key bacterial proteins
Deliver oxygen and nutrients
Recruit immune defenses to the injured tissue
Transport chemical factors essential for tissue recovery
