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

Microorganisms and Disease
Type III secretion systems are used to inject "effector" proteins directly into a host cell. Salmonella uses a type III secretion system to help the pathogen to

survive within macrophages
survive the acid pH of the stomach
secrete LT (heat labile toxin) and ST (heat stable toxin) into the lumen of the intestine
activate T cells to proliferate and secrete cytokines

ANSWER DOWNLOAD EXAMIANS APP

Microorganisms and Disease
Cholera toxin is an A-B type toxin in which the B portions bind to a receptor on a host cell and the A portion enters the cell to cause

ADP ribosylation of guanylate cyclase that stimulates production of cGMP
ADP ribosylation of a G protein that locks it into an active form that stimulates adenylate cyclase to make cAMP
cleavage of rRNA that results in disruption of ribosome function
ADP ribosylation of adenylate cyclase that stops production of cAMP

ANSWER DOWNLOAD EXAMIANS APP

Microorganisms and Disease
The "A" subunit of diphtheria toxin

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

ANSWER DOWNLOAD EXAMIANS APP

Microorganisms and Disease
Prontosil is

not used as an antibacterial agent
an effective antibacterial both in animals as well as in in-vitro cultures
an effective antibacterial when used in in-vitro cultures
an effective antibacterial when used in animals

ANSWER DOWNLOAD EXAMIANS APP