Cell Signalling and Transduction
In terms of cell communication, what do bacterial pathogens such as cholera and anthrax have in common?

They alter the chemical structure of key signaling molecules
They prevent the production of key signaling molecules
They destroy the receptors for key signaling molecules
They block the normal functioning of signal transduction mechanisms

ANSWER DOWNLOAD EXAMIANS APP

Cell Signalling and Transduction
The signaling molecules called steroid hormones

bind to cell surface receptors to trigger chemical cascades
are made in one location of the body but have their effects some distance away
never enter the blood of humans
are hydrophilic and so cannot penetrate the plasma membrane

ANSWER DOWNLOAD EXAMIANS APP

Cell Signalling and Transduction
cAMP and cGMP are derived from

None of these
ATP and GTP by the actions of adenylate cyclase and guanylate cyclase respectively
GTP and ATP by the actions of adenylate cyclase and guanylate cyclase respectively
ATP and GTP by the actions of guanylate cyclase and adenylate cyclase respectively

ANSWER DOWNLOAD EXAMIANS APP

Cell Signalling and Transduction
A cell is known to respond to a particular signaling molecule. Which of the following must be true of this cell?

It is in the heart muscle
It contains the receptor for the signaling molecule
It is incapable of signal transduction
It is also the site of production for the signaling molecule

ANSWER DOWNLOAD EXAMIANS APP