Exam 2: Quizzes Flashcards by Aleksandra Grigoryants

Which of the following describes viruses?

They are made up exclusively of obligate, intracellular parasites.

How well did you know this?

Not at all

Perfectly

The correct order of events in viral replication is:

adsorption, penetration, replication, assembly, release

How well did you know this?

Not at all

Perfectly

The host range of a virus is mainly determined by

the ability to dock with host proteins during adsorption

How well did you know this?

Not at all

Perfectly

Which of the following is NOT an example of a possible genome found inside a virus?

Question 4 options:

double stranded DNA

single stranded DNA

double stranded RNA

single stranded RNA

All of these are possible genome components of certain viruses

How well did you know this?

Not at all

Perfectly

Where should a specimen be collected from if a viral infection is suspected?

They should be collected from the affected site

How well did you know this?

Not at all

Perfectly

Which of the following is NOT a method used to diagnose a viral infection?

PCR

Enzyme Immunoassays

Direct fluorescent antibody staining

Serology

Cell culture techniques to grow the virus

All of the methods listed may be used to diagnose a viral infection.

How well did you know this?

Not at all

Perfectly

Antiviral therapies normally target

The replication cycle of the virus

How well did you know this?

Not at all

Perfectly

SARS-CoV-2 causes COVID-19.

true

How well did you know this?

Not at all

Perfectly

SARS-CoV-2 does not have an envelope making it harder to deactivate.

t/f

false, covid19 is enveloped

How well did you know this?

Not at all

Perfectly

There have never been any other coronavirus outbreaks in the world besides COVID-19.

t/f

false

2002-SARS
2012-MERS

How well did you know this?

Not at all

Perfectly

Everyone that is infected with SARS-CoV-2 will have a fever.

t/f

false, symptoms vary

How well did you know this?

Not at all

Perfectly

Which of the following is no longer used as a major criterion for viral classification and taxonomy?

disease caused

How well did you know this?

Not at all

Perfectly

Which of the following virulence factors is not associated with Staphylococcus aureus?

endotoxins

How well did you know this?

Not at all

Perfectly

How do staphylococci cause the epidermal layer of the skin to slough off and cause Scalded Skin Syndrome?

they produce exfoliative toxin, which is an epidermolytic toxin

How well did you know this?

Not at all

Perfectly

Where is the primary reservoir for Staphylococcus aureus?

nares

How well did you know this?

Not at all

Perfectly

The development of staphylococcal infection is determined by:

virulence of strain
size of inoculum
status of host’s immune system

How well did you know this?

Not at all

Perfectly

The staphylococcal species that is associated with urinary tract infection in young, sexually active females is

Staphylococcus saprophyticus

How well did you know this?

Not at all

Perfectly

What antibiotic is used for detection of methicillin resistant Staphylococcus aureus?

Oxacillin

How well did you know this?

Not at all

Perfectly

A women goes to the doctor complaining of large, raised, painful, suppurative abscesses on her leg. The woman does not have a fever, but you can see that she has inflammation of the skin and subcutaneous tissue on her leg. What is the name of the lesions on her leg, and what organism causes this type of lesion?

Staphylococcus aureus and furuncles

How well did you know this?

Not at all

Perfectly

All of the following staphylococci are coagulase-positive, except

Staphylococcus epidermidis

How well did you know this?

Not at all

Perfectly

This staphylococcal species produces wide zones of beta hemolysis on 5% sheep blood agar.

S. aureus

How well did you know this?

Not at all

Perfectly

A young, healthy woman was rushed to the hospital with a high fever, hypotension, and shock. She had not been feeling well that day, but her condition progressively worsened throughout the day. She was feeling fine until a couple of days after she started menstruating. What condition could this woman be exhibiting?

TSS - toxic shock syndrome

How well did you know this?

Not at all

Perfectly

What test differentiates staphylococci from streptococci?

catalase

How well did you know this?

Not at all

Perfectly

Streptococci are commonly classified using all of the following methods except:

flagellar antigens.

How well did you know this?

Not at all

Perfectly

Streptococci are commonly classified by which methods?

- physiological characteristics - serological grouping or typing of C carbohydrate -biochemical characteristics

Which virulence factor helps Streptococcus pyogenes evade phagocytosis and adhere to mucosal cells?

M protein

Which organism causes scarlet fever?

Streptococcus pyogenes

Which species is screened for near the end of pregnancy to prevent infection of the baby during delivery?

Streptococcus agalactiae

Streptococcus pneumoniae can cause all the following infections except:

pharyngitis

Streptococcus pneumoniae can cause all the following infections:

- pneumonia - bacteremia - meningitis

Which of the following organisms form grayish white colonies surrounded by a small zone of β-hemolysis on sheep blood agar?

Streptococcus agalactiae

Group A streptococcal disease can cause two serious complications of infection. These are

acute glomerulonephritis and rheumatic fever

Which of the following is the drug of choice for treating most streptococcal infections?

penicillin

A microbiologist is reading a sputum culture on the bench. There is growth on the SBA and chocolate (CHOC) plates, but no growth on the MacConkey (MAC) plate. The colonies growing on the SBA have produced a wide, deep, clear zone of β-hemolysis around and under the colonies. What organism could this be?

Streptococcus pyogenes

A father brings his son to his doctor with the following symptoms: sluggishness with a fever of 38° C (100.5° F) for a week. His tonsils were red and the back of his throat turned a gray color with a membrane on it. What disease should the physician suspect?

diphtheria

To determine if the strain of Corynebacterium diphteriae under investigation is toxigenic, which test should be performed?

Elek test

Several picnic goers came down with gastroenteritis. The food, hot dogs, were cultured on SBA for 24 hours. There were small, round, smooth, translucent colonies surrounded by a narrow zone of β-hemolysis. A Gram stain showed gram + coccobacilli. Motility medium showed an umbrella pattern of motility at room temperature. What organism was isolated as the cause of the illness?

Listeria monocytogenes

Which of the following organisms has morphology best described as: square-ended, large, gram+ rods that appear like bamboo?

Bacillus anthracis

Which of the following species is a relatively common cause of food poisoning?

Bacillus cereus

Neisseria species are usually all of the following except:

motile

Neisseria species are usually all of the following:

- catalase positive - aerobic - oxidase positive

Which of the following is NOT a method that may be used in identifying Neisseria gonorrhoeae? Oxidase test Nucleic acid amplification test Gram Staining Coagglutination All of the methods listed may be used in the identification / diagnosis of Neisseria gonorrhoeae

All of the methods listed may be used in the identification / diagnosis of Neisseria gonorrhoeae

How is Neisseria meningitidis spread?

respiratory droplets

Which of the following organisms is normally a commensal of the upper respiratory tract, but can cause an opportunistic infection in otherwise health children and the elderly?

Moraxella catarrhalis

Which of the following is not considered a nonpathogenic Neisseria spp.? N. cinerea N. weaveri N. mucosa N. polysaccharea All of the organisms listed are nonpathogenic Neisseria spp.

All of the organisms listed are nonpathogenic Neisseria spp.

While examining a stool culture, you notice a moist, mucoid, pink colony on MacConkey agar. What is most likely growing on the agar?

Klebsiella pneumoniae

Which of the following is NOT a general characteristic of enterics?

all are non-motile

Which of the following ARE general characteristic of enterics?

- ferments glucose - facultatively anaerobic - oxidase negative - gram-negative

What bacterium produces swarming colonies on nonselective media, such as sheep blood agar (SBA)?

Proteus mirabilis

The most common cause of community-acquired UTIs.

Escherichia coli

In the carrier state, where are pathogenic salmonella carried?

Gallbladder

Bacillary dysentery caused by this organism is marked by penetration of intestinal epithelial cells following attachment of the organisms to mucosal surfaces, local inflammation, shedding of the intestinal lining, and formation of ulcers that follow the epithelial penetration. What is this organism?

Shigella

Why can direct microscopy not be used to provide a presumptive identification of the enteric bacteria?

The microscopic characteristics are indistinguishable from other gram-negative bacteria.

All the following are biochemical features of Salmonella, except

lactose positive

All the following are biochemical features of Salmonella:

- indole negative - VP negative - hydrogen sulfide positive

What are the primary antigens used in serologic grouping of salmonellae?

Flagellar H antigen and somatic O antigen

What organism possesses the Vi antigen?

Salmonella Typhi

A child is diagnosed with meningitis and the doctor does a spinal tap. The cerebrospinal fluid (CSF) Gram stain shows many tiny gram-negative rods. What is the most probable identification of this organism?

Haemophilus influenzae serotype b

Which organism causes whooping cough?

Bordetella pertussis

What disease manifests in acute cases as a severe gastroenteritis, accompanied by vomiting followed by diarrheic stools that are described as rice water and occur 10 to 30 times a day?

cholera

Which of the following is the nonfermenter that is the leading cause of healthcare acquired pneumonia and bacteremia?

Pseudomonas aeruginosa

You have isolated an anaerobic bacterial species that is gram positive, bacillus in shape and forms spores. Which genus does this species probably belong to?

Clostridium

What is the causative agent of Lyme disease?

Borelia burgdorferi

Which organism produces infectious elementary bodies and noninfectious reticulate bodies?

Chlamydia

What is the causative agent behind Rocky Mountain spotted fever?

Rickettsia rickettsii

What is the smallest self-replicating, living, organism in nature?

Mycoplasma

Which staining procedure is usually used for Mycobacteria, because it provides the most reliable and useful results?

Acid Fast staining