11 Micro – Interactions Between Microbes and Humans

Infection occurs when
A. contaminants are present on the skin.
B. a person swallows microbes in/on food.
C. a person inhales microbes in the air.
D. pathogens enter and multiply in body tissues.
E. All of the choices are correct.

D. pathogens enter and multiply in body tissues.

The term infection refers to
A. microorganisms colonizing the body.
B. contact with microorganisms.
C. contact with pathogens.
D. pathogens penetrating host defenses.
E. None of the choices is correct.

D. pathogens penetrating host defenses.

Which is not terminology used for resident biota?
A. pathogenic biota
B. normal biota
C. indigenous biota
D. normal microbiota
E. commensals

A. pathogenic biota

Endogenous infectious agents arise from microbes that are
A. in food.
B. the patient’s own normal biota.
C. on fomites.
D. in the air.
E. transmitted form one person to another.

B. the patient’s own normal biota.

The human body typically begins to be colonized by its normal biota
A. before birth, in utero.
B. during and immediately after birth.
C. when a child first goes to school.
D. when an infant gets its first infectious disease.
E. during puberty.

B. during and immediately after birth.

Resident biota are found in/on the
A. skin.
B. mouth.
C. nasal passages.
D. large intestine.
E. All of the choices are correct.

E. All of the choices are correct.

Normal biota includes each of the following except
A. bacteria.
B. fungi.
C. protozoans.
D. viruses.
E. All of the choices are correct.

E. All of the choices are correct.

Each of the following are inoculation of normal biota to a newborn except
A. the birth process through the birth canal.
B. bottle feeding.
C. breast feeding.
D. contact with hospital staff.
E. All of the choices are correct.

E. All of the choices are correct.

The effect of "good" microbes against invading microbes is called
A. microbial antagonism.
B. endogenous infection.
C. infectious disease.
D. axenic.
E. gnotobiotism.

A. microbial antagonism.

All of the following genera are considered resident biota of skin sites except
A. Escherichia.
B. Staphylococcus.
C. Corynebacterium.
D. Micrococcus.
E. Candida.

A. Escherichia.

Opportunistic pathogens
A. cause disease in every individual.
B. cause disease in compromised individuals.
C. are always pathogens.
D. have well-developed virulence factors.
E. None of the choices is correct.

B. cause disease in compromised individuals.

Pathogenic microbes that cause disease in healthy people are called
A. opportunistic pathogens.
B. normal biota.
C. indigenous biota.
D. true pathogens.
E. micropathogens.

D. true pathogens.

Which of the following is not a factor that weakens host defenses against infections?
A. genetic defects in immunity
B. physical and mental stress
C. strong, healthy body
D. chemotherapy
E. old age

C. strong, healthy body

TORCH is an acronym that represents the most common
A. genera of resident biota.
B. sexually transmitted diseases.
C. portals of entry.
D. vectors.
E. infections of the fetus and neonate.

E. infections of the fetus and neonate.

The greatest number of pathogens enter the body through the
A. respiratory system.
B. gastrointestinal system.
C. urinary system.
D. genital system.
E. skin.

A. respiratory system.

An infectious agent that originates from outside the body is called
A. exogenous.
B. an exotoxin.
C. an enterotoxin.
D. endogenous.
E. axenic.

A. exogenous.

An infectious agent already existing on or in the body is called
A. exogenous.
B. an exotoxin.
C. an enterotoxin.
D. endogenous.
E. axenic.

D. endogenous.

The minimum amount of microbes in the inoculating dose is the
A. virulence factor.
B. indigenous biota.
C. infectious dose.
D. endotoxin.
E. minimal dose.

C. infectious dose.

Which of the following is not a method of adhesion?
A. fimbriae
B. surface proteins
C. specialized receptors
D. adhesive slime or capsules
E. cilia

E. cilia

Once a microbe has entered a host, what process performed by certain white blood cells will attempt to destroy the microbes?
A. phagocytosis
B. adhesion
C. encapsulation
D. margination
E. exocytosis

A. phagocytosis

Which of the following is not an anti-phagocytic factor?
A. secretion of slime
B. production of leukocidins
C. adhering to the host
D. secretion of a capsule
E. ability to survive intracellularly

C. adhering to the host

Virulence factors include all the following except
A. capsules.
B. ribosomes.
C. exoenzymes.
D. endotoxins.
E. exotoxins.

B. ribosomes.

Microbial hyaluronidase, coagulase, and streptokinase are examples of
A. adhesive factors.
B. exotoxins.
C. hemolysins.
D. antiphagocytic factors.
E. exoenzymes.

E. exoenzymes.

Exotoxins are
A. proteins.
B. only released after a cell is damaged or lysed.
C. antiphagocytic factors.
D. secretions that always target nervous tissue.
E. lipopolysaccharides.

A. proteins.

Enterotoxins are
A. virulence factors.
B. toxins that target the intestines.
C. proteins.
D. exotoxins.
E. All of the choices are correct.

B. toxins that target the intestines.

Which is mismatched?
A. fimbriae – adherence to substrate
B. capsules – antiphagocytic factor
C. coagulase – dissolve fibrin clots
D. leukocidins – damage white blood cells
E. hemolysins – damage red blood cells

C. coagulase – dissolve fibrin clots

Keritinase has the greatest effect on the
A. respiratory system.
B. gastrointestinal system.
C. urinary system.
D. genital system.
E. skin.

E. skin.

Mucinase has the greatest effect on the
A. respiratory system.
B. gastrointestinal system.
C. urinary system.
D. genital system.
E. skin.

B. gastrointestinal system.

Exotoxins
A. are secreted by pathogenic organisms.
B. are bound to the membrane of pathogenic organisms.
C. are bound to the cell wall of pathogenic organisms.
D. cause more damage than endotoxins.
E. are host specific.

A. are secreted by pathogenic organisms.

An endotoxin is
A. secreted by pathogenic organisms.
B. indicative of gram-negative organisms.
C. indicative of gram-positive organisms.
D. indicative of fungal infections.
E. indicative of viral infections.

B. indicative of gram-negative organisms.

_____ are toxins that are the lipopolysaccharide of the outer membrane of gram-negative cell walls.

A. Exotoxins
B. Endotoxins
C. Enterotoxins
D. Leukocidins
E. Hemolysins

B. Endotoxins

_____ are various bacterial enzymes that dissolve fibrin clots.
A. Coagulases
B. Mucinases
C. Keratinases
D. Kinases
E. Hyaluronidases

D. Kinases

Which of the following is the endotoxin?
A. hemolysin
B. hyaluronidase
C. toxinosis
D. collagenase
E. lipopolysaccharide

E. lipopolysaccharide

Hyaluronidase is a virulence factor in
A. amoebic dysentery.
B. ringworm.
C. clostridia.
D. cold virus.
E. diphtheria.

C. clostridia.

The suffix -emia means
A. blood.
B. a disease or morbid process.
C. an inflammation.
D. tumor.
E. pertaining to.

A. blood.

The stage of an infectious disease when specific signs and symptoms are seen and the pathogen is at peak activity is the
A. prodromal stage.
B. convalescent stage.
C. incubation period.
D. period of invasion.
E. None of the choices is correct.

D. period of invasion.

The time from when pathogen first enters the body and begins to multiply, until symptoms first appear is the
A. prodromal stage.
B. convalescent stage.
C. incubation period.
D. period of invasion.
E. None of the choices is correct.

C. incubation period.

The initial, brief period of early, general symptoms such as fatigue and muscle aches is the
A. prodromal stage.
B. convalescent stage.
C. incubation period.
D. period of invasion.
E. None of the choices is correct.

A. prodromal stage.

Which is mismatched?
A. secondary infection – infection spreads to several tissue sites
B. mixed infection – several agents established at infection site
C. acute infection – rapid onset of severe, short-lived symptoms
D. local infection – pathogen remains at or near entry site
E. toxemia – pathogen’s toxins carried by the blood to target tissues

A. secondary infection – infection spreads to several tissue sites

The subjective evidence of disease sensed by the patient is termed a/an
A. syndrome.
B. symptom.
C. sign.
D. pathology.
E. inflammation.

B. symptom.

The objective, measurable evidence of disease evaluated by an observer is termed a/an
A. syndrome.
B. symptom.
C. sign.
D. pathology.
E. inflammation.

C. sign.

Local edema, swollen lymph nodes, fever, soreness, and abscesses are indications of
A. toxemia.
B. inflammation.
C. sequelae.
D. a syndrome.
E. latency.

B. inflammation.

A symptom is a/an
A. objective indication of disease.
B. subjective indication of disease.
C. measurable by a health care personnel.
D. temperature.
E. None of the choices is correct.

B. subjective indication of disease.

A sign is a/an
A. objective indication of disease.
B. subjective indication of disease.
C. measurable by a health care personnel.
D. temperature.
E. Both objective indication of disease and measurable by a health care personnel are correct.

E. Both objective indication of disease and measurable by a health care personnel are correct.

Leukopenia is the _____ in the level of white blood cells in a patient.
A. elevation
B. stabilization
C. decrease

C. decrease

A _____ is the presence of small numbers of bacteria in the blood.
A. bacteremia
B. septicemia
C. viremia
D. None of the choices is correct.

A. bacteremia

Infections that go unnoticed because there are no symptoms are called
A. syndromes.
B. malaises.
C. inflammations.
D. asymptomatics.
E. secondary infections.

D. asymptomatics.

Which of the following is not a normal portal of exit for an infectious disease?
A. removal of blood
B. urogenital tract and feces
C. coughing and sneezing
D. skin
E. All of these are normal exit portals.

E. All of these are normal exit portals.

Which of the following is an example of sequelae?
A. headache from meningitis
B. difficulty swallowing from a Streptococcus infection
C. arthritis from Lyme disease
D. Diarrhea from Salmonella enteritidis infection
E. All of the choices are correct.

C. arthritis from Lyme disease

Diseases that cause long-term or permanent damage are called
A. latent.
B. sequelae.
C. direct.
D. indirect.
E. chronical.

B. sequelae.

The primary, natural habitat of a pathogen where it continues to exist is called the
A. fomite.
B. carrier.
C. vector.
D. reservoir.
E. source.

D. reservoir.

Someone who inconspicuously harbors a pathogen and spreads it to others is a
A. fomite.
B. carrier.
C. vector.
D. reservoir.
E. source.

B. carrier.

An animal, such as an arthropod, that transmits a pathogen from one host to another is a
A. fomite.
B. carrier.
C. vector.
D. reservoir.
E. source.

C. vector.

The intermediary object or individual from which the infectious agent is actually acquired is termed the
A. fomite.
B. carrier.
C. vector.
D. reservoir.
E. source.

E. source.

Reservoirs include
A. humans.
B. animals.
C. soil.
D. water.
E. All of the choices are correct.

E. All of the choices are correct.

Animals that participate in the life cycles of pathogens and transmit pathogens from host to host are
A. fomites.
B. aerosols.
C. mechanical vectors.
D. droplet nuclei.
E. biological vectors.

E. biological vectors.

A _____ is an infection indigenous to animals that can, on occasion, be transmitted to humans.
A. secondary infection
B. sequelae
C. nosocomial infection
D. zoonosis
E. None of the choices is correct.

D. zoonosis

_____ carriers are shedding and transmitting pathogens while they are recovering from an infectious disease.
A. Asymptomatic
B. Passive
C. Incubation
D. Chronic
E. Convalescent

E. Convalescent

______ carriers are shedding and transmitting pathogens a long time after they have recovered from an infectious disease.
A. Asymptomatic
B. Passive
C. Incubation
D. Chronic
E. Convalescent

D. Chronic

All infectious diseases
A. are contagious.
B. only occur in humans.
C. are caused by microorganisms or their products.
D. are caused by vectors.
E. involve viruses as the pathogen.

C. are caused by microorganisms or their products.

An inanimate object that harbors and transmits a pathogen is a
A. fomite.
B. carrier.
C. vector.
D. reservoir.
E. source.

A. fomite.

A laboratory technologist splashed a blood specimen onto his face, eyes, nose and mouth while performing a test in the lab. This specimen was from an HIV positive patient. If this blood exposure leads to HIV infection in the technologist, the transmission route is
A. direct.
B. fomite.
C. vehicle.
D. droplet nuclei.
E. aerosol.

C. vehicle.

The dried residues of fine droplets from mucus or saliva that harbor and transmit pathogens are
A. fomites.
B. aerosols.
C. mechanical vectors.
D. droplet nuclei.
E. biological vectors.

D. droplet nuclei.

Which of the following is a direct contact method of microbe transmission?
A. fomites
B. water
C. droplet nuclei
D. aerosols
E. droplets

E. droplets

Which of the following is transmission of disease from mother to fetus?
A. vertical
B. direct
C. vector
D. droplets
E. fomites

A. vertical

Nosocomial infections involve all the following except
A. are only transmitted by medical personnel.
B. often involve the patient’s urinary tract and surgical incisions.
C. the patient’s resident biota can be the infectious agent.
D. Escherichia coli and staphylococci are common infectious agents.
E. medical and surgical asepsis help lower their occurrence.

A. are only transmitted by medical personnel.

Which of the following is not a universal precaution used for handling patients and body substances?

A. mask and gloves
B. proper disposal of needles
C. healthcare worker with active lesions handling patients
D. hand washing
E. sterilizing or disinfecting dental hand pieces

C. healthcare worker with active lesions handling patients

When would Koch’s postulates be utilized?
A. determination of the cause of a patient’s illness in a hospital microbiology lab
B. development of a new antibiotic in a pharmaceutical lab
C. determination of the cause of a new disease in a microbiology research lab
D. formulation of a vaccine against a new pathogen in a genetic engineering lab
E. whenever the scientific method can not be used to investigate a microbiological problem

C. determination of the cause of a new disease in a microbiology research lab

The study of the frequency and distribution of a disease in a defined population is
A. pathology.
B. clinical microbiology.
C. medicine.
D. immunology.
E. epidemiology.

E. epidemiology.

The principal government agency responsible for tracking infectious diseases in the United States is

A. Centers for Disease Control and Prevention.
B. World Health Organization.
C. National Institutes of Health.
D. United States Department of Agriculture.
E. Infection Control Committee.

A. Centers for Disease Control and Prevention.

The number of new cases of a disease in a population over a specific period of time compared with the healthy population is the
A. mortality rate.
B. morbidity rate.
C. incidence rate.
D. prevalence rate.
E. epidemic rate.

C. incidence rate.

A disease that has a steady frequency over time in a particular geographic location is
A. epidemic.
B. endemic.
C. pandemic.
D. sporadic.
E. chronic.

B. endemic.

The total number of deaths in a population due to a disease is the _____ rate.
A. morbidity
B. mortality
C. incidence
D. endemic
E. pandemic

B. mortality

The number of persons afflicted with an infectious disease is the _____ rate.
A. morbidity
B. mortality
C. incidence
D. endemic
E. pandemic

A. morbidity

What is one goal of the Human Microbiota Project?
A. to sequence the DNA of all microorganisms
B. to study the prevalence of disease
C. to study microorganisms in their natural habitat
D. to provide comprehensive characterization of microbiota relating to human health and disease
E. to discover new organisms in extreme habitats

D. to provide comprehensive characterization of microbiota relating to human health and disease

Under certain circumstances, a person’s resident biota can be opportunistic pathogens.

TRUE

Most of the skin’s resident biota are found in the uppermost, superficial layers of the epidermis.

TRUE

The virulence factors of a pathogen are established by how strong or weak a patient’s body defenses are at the time of infection.

FALSE

The Centers for Disease Control and Prevention assigns the most virulent microbes known to cause human disease to biosafety level 4.

TRUE

A fetus can get an infection when a pathogen in the mother’s blood is capable of crossing the placenta to the fetal circulation and tissues.

TRUE

When an infected person is in the incubation period, that person cannot transmit the pathogen to others.

FALSE

Septicemia means that a pathogen is present and multiplying in the blood.

TRUE

Latency is a dormant state of an infectious agent.

TRUE

Fomites, food, and air serve as indirect transmission routes of pathogens.

TRUE

Koch’s postulates are easily satisfied for viral diseases.

FALSE