Microorganisms and Disease
The influenza vaccine is administered each year because

it is a polysaccharide vaccine that does not confer long-term protection
the vaccine is sufficiently toxic to make it necessary to administer only a small amount at any one time
mutations in the viral hemagglutinin may allow the virus to evade the immune response elicited by previous vaccines
None of these

ANSWER DOWNLOAD EXAMIANS APP

Microorganisms and Disease
A major difference between EHEC and EPEC is

EHEC possesses a type III secretion system and EPEC does not
EHEC secretes a Shiga-like toxin and EPEC does not
EPEC rearranges host cell actin and EHEC does not
EPEC passes through the placenta to infect the fetus and EHEC does not

ANSWER DOWNLOAD EXAMIANS APP

Microorganisms and Disease
The "A" subunit of diphtheria toxin

forms cAMP that leads to fluid accumulation
binds host cell receptors found on heart cells
lysis macrophages with the release of cytokines
cause ADP ribosylation of a factor involved in protein synthesis

ANSWER DOWNLOAD EXAMIANS APP

Microorganisms and Disease
Which of the following is common in the disease caused by Coryne-bacterium diphtheriae and Bacillus anthracis?

Both organisms cause skin and respiratory tract infections
Both organisms are gram-positive spore formers
Diphtheria toxin and edema toxin are ADP ribosylating toxins
The most serious disease symptoms are the direct result of toxin action

ANSWER DOWNLOAD EXAMIANS APP

Microorganisms and Disease
What is common in catheters and ventilators?

Bacteria responsible for associated infections are usually susceptible to antibiotics
They bypass important defenses of the body
They predispose patients to viral rather than bacterial infections
They are used primarily in neonatal intensive care units

ANSWER DOWNLOAD EXAMIANS APP