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

They block the normal functioning of signal transduction mechanisms
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

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Cell Signalling and Transduction
Why is it that inhaling nitric oxide reduces blood pressure only in the lung tissue and not elsewhere in the body*?

Because nitric oxide cannot cross cell membranes and enter the blood
Because nitric oxide breaks down quickly and thus cannot travel far
Because other body tissues use a different signaling molecule
None of these

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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

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Cell Signalling and Transduction
A signal cascade induced by adrenaline or thyroxine

involves the activation of a G protein
All of these
results in the activation of a sequence of enzymes needed for the cell effect
must begin with receipt of the signal molecule by a surface receptor

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Cell Signalling and Transduction
When a __________ reaches its __________ , there is a specific means of receiving it and acting on the message. This task is the responsibility of specialized proteins called __________ .

kinase; receptor; proteases
signaling molecule; target cell; receptors
signaling molecule; target cell; G proteins
signaling molecule; receptor; G proteins

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