Nitric oxide is a signal molecule that can

a. bind to surface receptors and activate second messengers.
b. bind to surface receptors and open ion channels.
c. diffuse across cell membranes and bind to receptors that regulate transcription.
d. diffuse across cell membranes and directly alter the activity of intracellular enzymes.


Ans: d. diffuse across cell membranes and directly alter the activity of intracellular enzymes.

Biology & Microbiology

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