Cell Signalling and Transduction
The binding of ligands to many G-proteins linked receptors leads to shortlived

increase in the concentration of certain extracellular signaling molecules called first messenger
increase in the concentration of certain intracellular signaling molecules called second messenger
decrease in the concentration of certain intracellular signaling molecules called second messenger
decrease in the concentration of certain extracellular signaling molecules called first messenger

ANSWER DOWNLOAD EXAMIANS APP

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

ANSWER DOWNLOAD EXAMIANS APP

Cell Signalling and Transduction
Self-phosphorylation is an excellent mechanism for triggering specific catalytic function of the proteins involved in signal cascades because it

allows hydrophilic signaling molecules to cross the plasma membrane
changes the shape and thus the enzymatic activity of the proteins involved
makes the receptor more likely to capture the signaling, molecule
None of these

ANSWER DOWNLOAD EXAMIANS APP

Cell Signalling and Transduction
In the signal transduction mechanism known as protein phosphorylation

receptor kinases play a key role in triggering the signal cascade
the signaling molecule binds to a surface receptor
phosphorylated proteins act with enzymes to trigger the signal cascade
All of these

ANSWER DOWNLOAD EXAMIANS APP