Which of the following is NOT an example of symbiosis?

A) bacteria in the human colon

B) tapeworm in the human intestine

C) tuberculosis in the human lung

D) protozoa in termites

E) microbes passing across the placenta to the fetus

E) microbes passing across the placenta to the fetus

Mutualism is a relationship

A) that sometimes provides benefits for both members such that one or both parties cannot live without the other.

B) where only one member derives benefit from the other.

C) where one member of the relationship may kill the other.

D) where one member of the relationship benefits without hurting the other.

E) where it is hard to prove the benefits or disadvantages one member of the relationship may

provide for the other.

A) that sometimes provides benefits for both members such that one or both parties cannot live without the other

A protozoan and its resident bacteria invade the body of a worm. The bacteria release toxins

and exoenzymes that immobilize and digest the worm, and the protozoan and bacteria absorb the

nutrients produced. The relationship between the protozoan and the bacteria would best be

described as

A) commensalism.

B) mutualism.

C) parasitism.

D) both commensalism and parasitism.

E) a nonsymbiotic relationship.

B) mutualism.

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) a parasite.

B) resident microbiota.

C) a mutualist symbiotic partner.

D) transient microbiota.

E) both resident microbiota and opportunistic pathogen.

E) both resident microbiota and opportunistic pathogen.

Chagas' disease is transmitted by a bug with mouthparts that penetrate blood vessels. Which

type of exposure does this represent?

A) mucous membrane portal

B) parenteral route

C) skin portal

D) contact

E) fomite

B) parenteral route

Symptoms are

A) subjective characteristics of a disease that only the patient can feel.

B) objective manifestations of a disease that can be measured.

C) objective manifestations of a disease that can be observed by others.

D) characteristics of a disease, such as sweating.

E) laboratory tests used to diagnose a disease.

A) subjective characteristics of a disease that only the patient can feel

Axenic systems of the body include

A) the nasal cavity.

B) the mouth.

C) the urethra.

D) the kidneys.

E) the conjunctiva of the eye.

D) the kidneys.

In which of the following do the mucous membranes serve as a portal of entry for disease?

A) A pathogen crosses from the mother to the fetus by way of the placenta.

B) A pathogen is introduced into the body when the person rubs the eye with contaminated

fingers and the pathogen is washed into the nasal cavity by way of tears.

C) A person is bitten by a mosquito that carries the malaria parasite.

D) Fungi digest the outer layer of the skin.

E) A person receives an injection with a contaminated needle.

B) A pathogen is introduced into the body when the person rubs the eye with contaminated fingers and the pathogen is washed into the nasal cavity by way of tears.

Which of the following statements regarding the demonstration of the etiology of disease is

FALSE?

A) The suspect agent must be present in all cases of disease.

B) The suspect agent must cause the disease under investigation when introduced into a

susceptible host organism.

C) The suspect agent must be isolated and cultured in the laboratory.

D) It must be possible to reisolate the suspect agent from the infected experimental host.

E) The suspect agent must be the only potential pathogen present in disease cases.

E) The suspect agent must be the only potential pathogen present in disease cases.

Which of the following situations is NOT a way in which a baby acquires normal

microbiota?

A) The baby acquires the residential microbiota in the colon after the first meal.

B) Staphylococcus epidermidis is transferred from the hospital staff to the newborn after

delivery.

C) Microbes cross the placenta during pregnancy.

D) Microorganisms grow in the respiratory tract after the baby's first breath.

E) Microbes enter the nose and mouth when the baby is in the birth canal.

C) Microbes cross the placenta during pregnancy.

Which of the following situations might cause normal microbiota to become opportunistic

pathogens?

A) growth of microbes on the surface of intact skin

B) growth of microorganisms on the excreted cellular wastes and dead cells in the large intestine

C) treatment of a cancer patient with radiation

D) growth of Lactobacillus on the surface of teeth

E) presence of Entamoeba in the lumen of the sigmoid colon

C) treatment of a cancer patient with radiation

Which of the following is considered part of the indigenous microbiota of the female

reproductive system?

A) Candida

B) Lactobacillus

C) E. coli

D) Bacteroides

E) both Candida and Lactobacillus

E) both Candida and Lactobacillus

Which of the following is an example of an exotoxin?

A) neurotoxins

B) coagulase

C) lipid A

D) streptokinase

E) collagenase

A) neurotoxins

Among the virulence factors produced by Staphylococcus aureus are hemolysin, coagulase,

hyaluronidase, and enterotoxin. Which of these factors contribute(s) to the ability of S. aureus to

invade the body?

A) coagulase

B) enterotoxin

C) hemolysin

D) hyaluronidase

E) coagulase and hemolysin

D) hyaluronidase

Which of the following stages of an infectious disease is the most severe?

A) the incubation period

B) the prodromal period

C) the illness period

D) the decline period

E) the convalescence period

C) the illness period

Which of the following is transmitted by the parenteral route?

A) ringworm

B) warts

C) gonorrhea

D) yellow fever

E) cutaneous anthrax

D) yellow fever

Which of the following is considered a mechanical vector transmission?

A) cockroach transmission of Shigella

B) mosquito transmission of Plasmodium

C) flea transmission of Yersinia

D) tsetse fly transmission of Trypanosoma

E) louse transmission of Rickettsia

A) cockroach transmission of Shigella

Which of the following is a sign of disease?

A) headache

B) dizziness

C) fever

D) nausea

E) cramps

C) fever

A nosocomial disease is a disease acquired

A) by being bitten by an infected insect.

B) by eating contaminated food.

C) by using a contaminated needle.

D) in a health care facility.

E) by having unprotected sexual intercourse.

D) in a health care facility.

Diseases that are induced by modern medical procedures are referred to as

A) iatrogenic infections.

B) exogenous infections.

C) opportunistic infections.

D) endogenous infections.

E) subacute infections.

A) iatrogenic infections.

Which of the following is a major source of disease transmission in the world?

A) contaminated fomites

B) fecal-oral infection

C) waterborne transmission

D) foodborne transmission

E) bodily fluid transmission

B) fecal-oral infection

Acne is an example of a

A) contagious disease.

B) subacute disease.

C) chronic disease.

D) noncommunicable disease.

E) latent disease.

D) noncommunicable disease.

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.

A) epidemic

B) endemic

C) sporadic

D) pandemic

E) opportunistic

A) epidemic

The incidence of tuberculosis in the year 2000 in the United States was 12.43/100,000 cases.

This means

A) 12.43 in every 100,000 people in the United States had tuberculosis in the year 2000.

B) 12.43 of every 100,000 people died of tuberculosis in the U.S. in the year 2000.

C) there were 12.43 new cases of tuberculosis for every 100,000 people in the United States in

the year 2000.

D) there were 12.43 tubercle bacilli per 100,000 microbes in the United States in the year 2000.

E) 12.43 of every 100,000 cases of tuberculosis were treated in the United States in the year

2000.

C) there were 12.43 new cases of tuberculosis for every 100,000 people in the United States in

the year 2000.

The index case is the first case of a disease

A) identified in a given area or population.

B) in a given area or population resulting in patient death.

C) in a given area or population in which the patient recovers.

D) transmitted to another individual in a given area or population.

E) to be successfully treated in a given area or population.

A) identified in a given area or population.

In the wake of the cyclone that hit Myanmar (Southeast Asia) in 2008, there were

widespread reports of typhoid fever. Which of the following was the most likely mode of

transmission?

A) mosquitoes

B) aerosols

C) contact

D) contaminated water

E) flies

D) contaminated water

Which of the following types of epidemiology applies Koch's postulates to study a disease?

A) experimental epidemiology

B) descriptive epidemiology

C) analytical epidemiology

D) systemic epidemiology

E) retrospective epidemiology

A) experimental epidemiology

Aerosols may be involved in __________ transmission of pathogens.

A) droplet

B) direct

C) vector

D) fecal-oral

E) waterborne

A) droplet

Fomites are

A) insects that transmit pathogens from an infected host to a noninfected host.

B) inanimate objects involved in the indirect contact transmission of pathogens.

C) fecal material from infected hosts.

D) animal sources for human pathogens.

E) silent carriers of infectious diseases.

B) inanimate objects involved in the indirect contact transmission of pathogens.

Which of the following pairings of microbe and disease was DISPROVEN using Koch's

postulates?

A) HIV and AIDS

B) Mycobacterium leprae and leprosy

C) Hepatitis B and D and liver cancer

D) Varicella-zoster virus and chickenpox

E) Haemophilus influenzae and the flu

E) Haemophilus influenzae and the flu

Which of the following is NOT an example of a zoonosis?

A) typhus

B) rabies

C) typhoid fever

D) salmonellosis

E) anthrax

C) typhoid fever

Which of the following is the correct sequence of a disease process?

A) convalescence, incubation, prodromal period, illness, decline

B) prodromal period, convalescence, incubation, illness, decline

C) incubation, convalescence, prodromal period, illness, decline

D) incubation, prodromal period, illness, decline, convalescence

E) illness, convalescence, incubation, prodromal period, decline

D) incubation, prodromal period, illness, decline, convalescence

Which of the following is NOT considered a type of vehicle transmission of a pathogen?

A) via animals

B) via air

C) via drinking water

D) via food

E) via body fluid

A) via animals

Clostridium difficile is the causative agent of

A) pseudomembranous colitis.

B) botulism.

C) tetanus.

D) cholera.

E) bed sores.

A) pseudomembranous colitis.

Which of the following combinations of pathogen and virulence factor is correct?

A) Neisseria gonorrhoeae and endotoxin

B) Streptococcus pyogenes and protein M

C) Staphylococcus aureus and neurotoxin

D) Gram-positive bacteria and lipid A

E) Escherichia coli and cytotoxin

B) Streptococcus pyogenes and protein M

A pathogen is best described as

A) a microorganism that remains with the person throughout life.

B) any microorganism that causes disease.

C) an organism that remains in the body for a short time.

D) a microorganism that may cause a disease under certain circumstances.

E) a source of microbial contamination.

B) any microorganism that causes disease.

Microbes known as transient microbiota are

A) microorganisms that remain with the person throughout life.

B) microorganisms that may cause a disease under certain circumstances.

C) organisms that remain in the body for a short time.

D) unsuccessful microbial invaders because of the presence of preexisting microbes.

E) sources of microbial contamination.

C) organisms that remain in the body for a short time.

Opportunistic microorganisms are

A) a source of microbial contamination.

B) organisms that remain in the body for a short time.

C) any microorganism that causes disease.

D) microorganisms that may cause a disease under certain circumstances.

E) organisms that remain in the body for a short time and cause disease.

D) microorganisms that may cause a disease under certain circumstances.

Organisms that are resident microbiota are best described as

A) microorganisms that remain with the person throughout life.

B) any microorganisms that cause disease.

C) organisms that remain in the body for a short time.

D) microorganisms that may cause a disease under certain circumstances.

E) microorganisms that never cause disease.

A) microorganisms that remain with the person throughout life.

The condition known as mutualism is

A) a relationship between two organisms where only one member benefits and the other is

unharmed.

B) a relationship between two organisms where one member harms the other.

C) a relationship between two organisms where both members benefit.

D) an environment that is free of microbes.

E) a relationship in which two organisms coexist only for a short time.

C) a relationship between two organisms where both members benefit.

Commensalism is best described as

A) an unsuccessful microbial invasion due to the presence of preexisting microbes.

B) a relationship between two organisms where only one member benefits and the other is

unharmed.

C) a relationship between two organisms where both members benefit.

D) a relationship in which a microorganism causes disease.

E) a source of contamination.

B) a relationship between two organisms where only one member benefits and the other is unharmed.

The condition called parasitism is characterized as

A) a relationship between two organisms where only one member benefits and the other is

unharmed.

B) a relationship between two organisms where both members benefit.

C) a nonsymbiotic relationship.

D) an unsuccessful microbial invasion due to the presence of preexisting microbes.

E) a relationship between two organisms where one member harms the other.

E) a relationship between two organisms where one member harms the other.

An axenic environment is one

A) in which microorganisms remain with the person throughout life.

B) that is free of microbes.

C) that is a source of contamination.

D) in which microorganisms remain present only for a short time.

E) contaminated by microbial toxins.

B) that is free of microbes

The condition known as microbial antagonism may be defined as

A) microorganisms that remain with a person throughout life.

B) a relationship between two organisms where one member harms the other.

C) a relationship between two organisms where only one member benefits.

D) an unsuccessful microbial invasion due to the presence of preexisting microbes.

E) a relationship between two organisms where both members benefit.

D) an unsuccessful microbial invasion due to the presence of preexisting microbes.

A reservoir is

A) a source of microbial contamination.

B) an environment that is free of microbes.

C) any microorganism that causes disease.

D) a condition in which organisms remain in the body for a short time.

E) a source of microbes for laboratory testing.

A) a source of microbial contamination.

In commensalism, one member of the relationship harms the other.

FALSE

Normal microbiota may cause disease if they are introduced into an unusual site in the body.

TRUE

A syndrome is a group of symptoms and signs that collectively characterize a particular

disease.

TRUE

All diseases go through the stages known as incubation period, prodromal period, and illness.

FALSE

Fomites cause disease by direct contact.

FALSE

A common cold is an example of a chronic disease.

FALSE

Infection from a mosquito bite is an example of the parenteral route of transmission.

TRUE

An antiphagocytic factor is one that permits pathogens to avoid attack by macrophages.

TRUE

Koch's postulates can be applied to every infectious disease to identify its causative pathogen.

FALSE

An infection always leads to disease.

FALSE

Toxins that affect the lining of the gastrointestinal tract are __________.

Answer: enterotoxins

E. coli in the colon is an example of __________ microbiota.

Answer: resident

Places in the body where there is no normal microbiota are referred to as __________.

Answer: axenic

Neurotoxins interfere with the __________ function of the host.

Answer: nerve

The __________ period is the time between infection and the occurrence of the first

symptoms or signs of the disease.

Answer: incubation

Staphylococcus bacteria are commonly present in the human nasal cavity but rarely cause

disease of the upper respiratory system. This situation is an example of __________.

Answer: commensalism

Lipid A is an __________ that stimulates the body to release chemicals that cause fever,

inflammation, diarrhea, hemorrhaging, shock, and blood coagulation.

Answer: endotoxin

Diseases that are naturally spread from their usual animal hosts to humans are known as

__________.

Answer: zoonoses

Spread of pathogens from one host to another by fomites is an example of __________

contact transmission.

Answer: indirect

Biological __________ not only transmit pathogens, but also serve as hosts for the

manipulation of the pathogen during some phase of the pathogen's life cycle.

Answer: vectors

The bacterium that causes cholera is capable of living independently in freshwater. As a

consequence, cholera epidemics primarily involve __________ reservoirs.

Answer: nonliving

The study of the cause of disease is known as __________.

Answer: etiology

The hepatitis C virus normally establishes a(n) __________ infection and may be

asymptomatic for a decade.

Answer: latent

The study of when and where diseases occur is known as __________ epidemiology.

Answer: descriptive

15) In 2% of pregnancies, pathogens cross the __________ and infect the embryo or fetus.

Answer: placenta

The __________ route is not a portal route of entry of a pathogen per se, but rather a way of

circumventing the usual portals.

Answer: parenteral