Voltage gated and ligand gated channels

Question

compare and contrast ligand gated(in cell body and dendrites) and voltage gated channels (in axons) in relation to resting membrane potential

Answer 1

Normally, ligand gated channels are responsible for the creation of a graded potential as opposed to an action potential.

When a signal reaches a synapse usually a neurotransmitter is released, for example, acetylcholine (ACh). The receptors, or ligand gated channels, in the post synaptic cell open to allow for the flow of ions into and out of the cell. This creates a change in the membrane potential. The summation of these changes across the cell body and dendrites is analyzed by the neuron and the decision to create an action potential is made.

The action potential travels down the axon. There the strength of the signal is always the same. The signal itself opens the next channels, the voltage gated channels, and the signal propagates down the axon where the cycle repeats itself.