OA study set

What is the significance of microorganisms containing a thick coats of peptidoglycan within the cell wall?

They are gram-positive bacteria.

Why are viruses considered acellular?

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?

Differential stain

A doctor prescribed antibiotics for a patient c/o runny nose, fever, aches and pain. 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, shigella, 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.

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

What is an example of vehicle transmission?

A person drinks untreated water on vacation and later has diarrhea and nausea.

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?

Protoza

A patient presents to the ED 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 disease, 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

Which 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-lectamase-producing pathogens cause public concern for a community?

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

Why are anti-helminth drugs difficult to produce?

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

Which pathogen is susceptible to beta-lactam microbials?

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?

Synergism

How can pathogens typically found in animal feces, such as hantavirus, 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 un-immunized members protected.

What does a stain that shows pink and green masses mean?

It is a positive endospore stain.

Which type of microorganism causes trichinellosis?

Parasite, by releasing larvae that encysts in muscles

Which virulence factor is produced by Protozoa?

Cysts

What does the presence of green and pink structures in a slide prepared with healed manchette green, washed, and counterstained with stained suggest?

The culture is a spore-former

What is the significance of the microbes tend within the domains Bacteria and Archaea?

They are prokaryotes and can carry out asexual reproduction.

Which bacterial virulence factor describes the alteration of the proteins on the membrane surface so the immune system will no longer recognize the threat?

Antigenic Variation

How are the roles of physical and chemical methods of microorganism control different in protecting a community from disease?

Physical methods are preventive, while chemical methods are reactionary treatments.

Which predictive methods could be used by public health organizations to prevent infectious disease problems?

Tracking the infection rates of notifiable diseases.

What do DNA vaccines work to protect against a future vial pathogen?

The DNA is transcribed and translated so that the host produces the viral antigens.

How do variolation and vaccination differ?

Only variolation uses uncompromised viruses

Which vaccine type does not prevent future infection?

Toxoid

Which vaccine type is made of whole pathogens?

Inactivated

What type of transmission is described by someone coughing on the person in front of them in line at the grocery store?

Direct Contact Transmission

Which advantage do live attenuated vaccines have over other options in the context of public health?

They result in long lasting immunity.

A patient has contracted a bacterial infection with multiple types of pathogens (gram-positive and gram-negative). Which kind of antimicrobial drug should be used to treat this patient?

Broad-spectrum antibiotics.

Why would antibiotics that target protein synthesis often be considered broad-spectrum?

Both gram-positive and gram-negative have the same protein synthesis machinery.

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?

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

Which type of vaccine promotes a low-level infection in the vaccinated person?

Attenuated

What do variolation and vaccination have in common?

They both lead to immunity.

Which of the following describes an example of indirect contact transmission?

An infected child touches a caregiver's phone, then the caregiver touches the phone before scratching their nose.

Why might a clinician request a gram stain prior to prescribing antibiotics?

Cell wall synthesis is a target of many antibiotics.

When would it be appropriate to treat a patient who has a bacterial infection with a bacteriostatic drug?

When the patient has a strong immune system.

Which type of microorganism can form endospores?

Bacteria

Laboratory personnel have identified a gram-positive, acid-fast positive, non-spore forming bacillus. Which trait allows the organism to be acid-fast positive?

Mycolic acid

How does the CDC (Centers for Disease Control) obtain information shout important infectious diseases incidence and prevalence?

Important infectious diseases are labeled as notifiable, and physicians are required lo report all cases.

Stains are often applied to increase the visibility of microscopic components or characteristics if the chromophore is the positively charged ion, the stain is classified as a basic dye, if the chromophore is the negatively charged ion, the stains considered an acidic dye. Which component of a bacterial cell would be stained by a basic dye?

The cell wall

What is the removal of pollutants or xenobiotics from the environment by bacteria called?

Bioremediation

What is the difference between gram-positive and gram-negative cells?

Gram-positive cells have thick peptidoglycan layers, while gram-negative calls have outer membranes containing lipopolysaccharides.

What is pathogenicity?

the ability to cause a disease

What is virulence?

the severity of a disease caused

What is a primary pathogen?

a pathogen that can cause disease in only non-immunocompromised people

What is a opportunistic pathogen?

a pathogen that can only cause disease in immunocompromised people