D311: Microbiology WGU OA

What is the significance of microorganisms containing a thick coat of peptldogiywn within the cell wall?

Microorganisms containing a thick coat of peptidoglycan within the cell wall are typically classified as gram-positive bacteria.

Why are viruses considered aceilular?

They cannot reproduce without a host.

What is the defining characteristic of eukaryotes?

They have a nucleus.

Which microorganism can cause vaginal yeast Infections and oral thrush?

Fungi

Why can It be difficult to determine the etiologic agent of a disease?

Some signs and symptoms can be caused by many different etiologic agents.

What kind of staining technique Is the acid-fast stain?

A doctor prescribed antibiotics for a patient complaining of runny nose. fever. and aches and pains. Which type of infection did the doctor suspect?

The doctor likely suspected a bacterial infection because antibiotics are not effective against viral infections.

A healthcare professional is treating a patient who developed a yeast infection after taking antibiotics. What type of medication should be prescribed to this patient?

Antifungals

Which structure promotes motility in Proteus. Shigelia. and Salmonella species. all of which can cause serious disease in humans?

Presence of flagella

Which bacterial virulence factor allows a strain to resist phagocytosis, increasing the organism's virulence?

Capsule production

Why is treating Haemophilus influenzae difficult?

The capsule is antiphagocytic.

How do pili aid pathogens in causing disease?

They cause pathogens to adhere to host cells.

Which virulence factor allows pathogens to penetrate the dermis and invade the body?

Bacterial enzymes

A bacterium from a deep-sea hydrothermal vent has been cultured. Which staining technique should be used to begin the process of species identification?

Gram staining

What does the presence of a clear area around a cell stained with India ink indicate about the cell?

The cell has a capsule.

How do basic stains work?

The positively charged stain is attracted to the negatively charged portion of the cell.

Which staining technique is used to distinguish bacteria based on their ability to produce structures that can survive extreme heat stress?

Endospore stain

Which aspect of a staining protocol enables dye to penetrate an endospore?

Heat

Why are the relationships between pathogenic microbes and their hosts considered parasitic?

The microbe benefits from the interaction while the host is harmed.

Which characteristic of dracunculiasis has been pivotal to the success of its eradication campaign?

Dracunculiasis has no animal reservoir.

Which type of organism would be most likely to grow on food stored in a refrigerator or freezer?

A psychrophile would be most likely to grow on food stored in a refrigerator or freezer as these microorganisms thrive in cold temperatures.

Staphylococcus epidermldls is a member of the human resident microbiota and considered part of the human innate immune system. S. epldermidis uses our dead skin cells as a source of nutrients. What type of relationship between S. epidermidis and humans is described above?

The type of relationship between Staphylococcus epidermidis and humans described above is "Commensalism," where one organism (S. epidermidis) benefits (uses dead skin cells) without harming the other organism (humans).

Commensalism

Why is the production of lactic acid by the resident microbe Lactobacillus Important to human health?

Lactic acid is important to human health because it inhibits the growth of pathogenic yeasts.

Which type of infections are prevented by proper sterilization of hospital equipment and healthcare worker handwashing?

Nosocomial infections are prevented by proper sterilization of hospital equipment and healthcare worker handwashing.

A patient Is determined to have contracted Lyme disease after being bit by an infected tick. What type of transmission is described in this scenario?

Vector transmission is described in this scenario.

Which is a description of vehicle transmission?

A person drinks untreated water on vacation and later has diarrhea and nausea is a description of vehicle transmission.

Which organism type contains species that perform adhesion through the unique use of its flagella to move out fluid from under a large adhesive disc, resulting in lower pressure to adhere to the intestinal lining?

Protozoa

A patient presents to the emergency department with high fever. difficulty breathing. vomiting, coughing up blood. and severe chest pain when inhaling. Which pathogen would the provider suspect?

Bacillus anthracis

Which activity of the complement system would be useful against an infection caused by a gram-negative bacterium?

Membrane attack complex

Which body system is protected by the ciliary escalator?

Respiratory

What is the role of global public health organizations in eradication of diseases, like polio?

Organize vaccination campaigns and programs

Malaria cases are routinely found in certain areas of the world but are not seen In other areas. How would malaria be described in those areas where it is found?

Endemic

A hospital notices an increase in patients being admitted with gastrointestinal symptoms and dehydration over a two-week period. An epidemiological analysis reveals that the cause is the same pathogen, but that none of the hospitalized individuals were ever in the same location at the same time. What is an explanation for this analysis?

These individuals all consumed contaminated food from a common manufacturing source.

Which action is an innate physical defense?

Mucous secretions trapping and removing microbes from the respiratory tract.

Which vaccine type would be effective against an organism that can produce a capsule?

Conjugate

Vhich protocol for microbial growth control leaves the least number of living cells?

Sterilization

Which type of microbial control is necessary for surgical equipment?

Sterilization

How are spore-forming bacteria killed to make canned foods safe for consumption?

Heat and pressure

Which type of microbial control is used in a variety of situations, from doorknobs to swimming pools to diaper cream. to prevent the growth and spread of microbes?

Phenolics

Why is boiling not used as a sterilization method In clinical settings?

Boiling is not effective against endospores.

Why do beta-lactamase-producing pathogens cause public concern for a community?

Beta-lactamase is an enzyme that protects the pathogen from some common antibiotics.

Why are antlhelmlnthlc drugs difficult to develop?

Helminths are eukaryotes, and it is difficult to develop medications with selective toxicity for them.

Which pathogen is susceptible to beta-lactam antimicrobials?

Prokaryotic pathogens are susceptible to beta-lactam antimicrobials.

Which process is targeted by antivirals?

Antivirals target the process of nucleic acid synthesis in viruses.

Which term describes how bacteriostatic antibiotics become bactericidal when the drugs are used together?

The term that describes how bacteriostatic antibiotics become bactericidal when used together is "Synergism."

How can pathogens typically found in animal feces, such as hantavlrus, be transmitted through air?

Dried fecal particles are carried on dust and inhaled by humans.

Which cellular component is conjugated to protein antigens to improve efficacy In the conjugate vaccine. especially for children under the age of two?

Capsule polysaccharide

What is the disadvantage of a live attenuated vaccine?

Risk of reversion

How do vaccines help the body fight against viruses?

By training the adaptive immune system

Which vaccine type would be useful against a toxin-producing strain of bacteria?

Toxoid vaccine

Which vaccine type would result in both a cell-mediated and humoral immune response because pathogens are able to grow in the host?

Attenuated viral vaccine

Why would conjugate vaccines have higher efficacy than a subunit vaccine for the same pathogen?

Conjugate vaccines combine an antigen that creates a weak immune response with an antigen that creates a strong immune response, which can result in higher efficacy compared to a subunit vaccine for the same pathogen.

When is herd immunity achieved?

Herd immunity is achieved when the immune portion of a population renders unimmunized members protected.