WGU D311: Microbiology with Lab: Section 2 Exam 2025 UPDATE/PRACTICE QUESTIONS AND CORRECT VERIFIED ANSWERS(complete solutions)ASSURED SUCCESS/GRADED A+!!!

What is a characteristic of rhizospheres?

The rhizosphere is where plants release organic compounds that can be metabolized by microbes into soil.

Which environment would contain microbes that are psychrophilic?

Glaciers

What is the role of nematodes in soil?

They prey on bacteria, smaller nematodes, fungi, and even plant roots.

Which eukaryote is responsible for producing antibiotics to ward off bacterial competitors?

Fungi

Which symbiotic relationship is an example of mutualism?

The relationship between humans and the Escherichia coli colonizing the human gut.

Which type of symbiotic relationship exists between the E. coli that inhibit the human gut and the humans who utilize the vitamin K produced by E. coli?

Mutualism

Describe resident microbiota.

Resident microbiota constantly live on the human body.

Which relationship is exhibited by intestinal E. coli and their human host?

Mutualism

Which type of disease is transmitted from animals to humans?

Zoonotic diseases

Which type of disease is acquired in hospital settings?

Nosocomial diseases

Which portal of exit can expel the most viral particles?

Respiratory

Which type of disease is sickle cell anemia?

Noninfectious

Which type of transmission occurs when tuberculosis is spread through small particles expelled by a cough?

Droplet transmission

Which type of transmission occurs when pathogens are spread from mother to child during breastfeeding?

Vertical direct contact transmission

Which type of transmission occurs when an arthropod carries a viral pathogen inside of its body?

Biological vector transmission

Which type of transmission occurs through contact with a fomite?

Indirect contact transmission

Which infected host would be considered a passive carrier?

A healthcare professional who does not wash their hands after seeing an infected patient.

How is Giardia lamblia, the causative of giardiasis, transmitted?

Contaminated food or water.

Which organism is the definitive of Toxoplasma gondii?

Cats

Which disease is transmitted by animals but not arthropods?

Rabies

How can adhesins be described?

Adhesins found on the surface of pathogens bind to receptors of hist cells.

Describe a portal of entry.

Body features through which pathogens can enter host tissue.

Pathogens produce proteins to prevent the fusion of the phagosomes and the lysosome (phagolysosome). Why does this virulence factor facilitate invasion?

It prevents the exposure of pathogens to lethal digestive enzymes.

Which action refers to a secondary infection?

An infection by one pathogen enables another pathogen to cause an infection.

What differentiates signs from symptoms of disease?

Signs are measurable; symptoms are subjective.

Which procedure does a clinician use to measure a symptom?

Asking patients to rate pain on a numerical scale.

During which stage of an infection does a patient feel the worst?

The period of illness stage

What defines the end of the incubation period for an infectious disease?

The appearance of nonspecific signs or symptoms of disease

How does the epidermis help prevent infection and disease?

It provides a harsh environment for most pathogens and periodically sheds.

How does the complement system contribute to the innate immune response?

It is composed of proteins that can be activated by the presence of pathogens to form the membrane attack complex (MAC).

Why are antimicrobial peptides (AMPs) considered an innate immune function?

AMPs are produced both routinely and as a response to pathogens.

Which terms refer to monocytes when they differentiate into tissue-specific phagocytes?

Macrophages and dendritic cells

What is specifically being reported if the Centers for Disease Control and Prevention reports 10,000 new cases of COVID-19?

Incidence

What is the difference between prevalence and incidence?

Prevalence refers to the total number of infections; incidence refers only to new cases.

Which term refers to a disease that occurs on a worldwide scale at a given time?

Pandemic

Why are etiologic agents significant to epidemiologists?

Etiologic agents are pathogens that cause disease.

Which kind of diseases must be reported to the Centers for Disease Control and Prevention in order to prevent future pandemics?

Notifiable diseases

How does the CDC obtain the latest data on typical illnesses to publish in the Morbidity and Mortality Weekly Report (MMWR)?

Through mandatory reporting of notifiable disease cases by healthcare providers.

What can cause an infectious disease to become a reemerging disease?

The responsible pathogen becomes drug resistant.

What does the WHO do to prevent future pandemics?

The WHO maintains a global alert and response system from data from multiple countries.

A patient taking the antibiotic cephalexin for a urinary tract infection developed severe diarrhea two days after completing the five-day course of treatment. What is an explanation for the development of this patient's diarrhea?

Cephalexin disrupted the normal intestinal microbiome.

Store-bought, packaged soil used to promote rapid plant growth was accidentally irradiated, thus killing the bacteria that had been in the soil. Which impact would this have on farmers?

Plants would die due to a lack of absorbable forms of nitrogen and phosphorus.

A hospital infection preventionist has instituted a policy to prevent nosocomial infections. Which guideline is an effective component of this policy?

Healthcare personnel must wear personal protective equipment at all times.

A family and its dog were hiking and swimming in the woods. Two days later, each family member developed a large bull's-eye lesion on their arm and the dog became anorexic and lethargic. Which control measure will be helpful to prevent the development of a future infection caused by the same microorganism?

The family immediately checks themselves and the dog for ticks after returning home.

A veterinarian diagnoses a dog with a zoonotic bacterial infection. Which precautions should the veterinarian advise for the caretaker?

Wash hands after touching the dog.

Viral epidemics concern public health department officials because some infected people do not show signs or symptoms of infection, whereas others have prolonged prodromal periods. What should public health officials do to minimize these causes for concern?

Test people who are asymptomatic

A contagious respiratory feline virus may reactivate a latent infection months to years after an initial infection. Which implication does this have for the management of cats in animal shelters?

Cats entering the shelter should be isolated from other sheltered cats.

Two spouses present to the emergency department because of difficulty swallowing, facial weakness on both sides of the face, and trouble breathing after consumption of spaghetti sauce made from canned tomatoes. The physician is aware of reports of similarly affected patients in nearby communities. What should be the physician's next step after treating these patients?

Contact the state department of public health

The varicella-zoster virus (chicken pox) is endemic in the US. What should physicians do to optimally minimize the risk of disease due to this virus?

Vaccinate those who have not already had chicken pox.

Miami-Dade County public health officials confirmed transmission of Zika virus by the local Aedes aegypti mosquito, but the virus had been previously transmitted by mosquitos only in Latin America and South America, where the virus is endemic. What can be done to mitigate the spread of the Zika virus so that it does not become endemic in the US?

Remove outdoor objects that may accumulate water because they serve as mosquito reservoirs.