Question

Which description of synapses is not correct? which description of synapses is not correct? second messengers can activate gene activities in the postsynaptic neuron. excitatory synapses cause depolarization. direct signaling involves the activation of g proteins. ionotropic receptors are ion channels that open and influence the polarization of the membrane?

Answer 1

The incorrect among the choices is "direct signaling involves the activation of g proteins"

This is incorrect because direct signaling does not involve the activation of g proteins rather it involves the activation of ion channels resulting to either an excitation reaction (depolarization of the membrane) or an inhibition reaction (hyperpolarization of the membrane); and this will ultimately affect the action of the organ the nerve is innervating.

Answer 2

I would like to believe that the answer to this question is the third option which is direct signaling involves the activation of G proteins. <em />In direct signaling ion channels that affect the polarization of the membrane are opened. The direct signaling pathway is local and therefore 2-AG binds only with a few neighboring synapses.