Question

Which statement is true regarding the neuron synapse?

a)The binding of a neurotransmitter always causes an excitatory effect on that cell, never inhibitory
b)Binding of a neurotransmitter on the postsynaptic neuron membrane can generate an action potential in that neuron
c)The human body only uses one type of neurotransmitter in all of its synapses
d)The presynaptic and postsynaptic neuron membranes are not physically separated

Answer 1

The effect of a neurotransmitter on the postsynaptic element depends on the receptor protein. Acetylcholine can cause depolarization or hyperpolarization depending on the type of muscarinic receptor it binds to.

Step-by-step explanation:

The effect of a neurotransmitter on the postsynaptic element is entirely dependent on the receptor protein. If there is no receptor protein in the membrane of the postsynaptic element, then the neurotransmitter has no effect. The depolarizing or hyperpolarizing effect is also dependent on the receptor. For example, when acetylcholine binds to the nicotinic receptor, the postsynaptic cell is depolarized because the receptor is a cation channel, allowing positively charged Na+ ions to enter the cell. However, when acetylcholine binds to the muscarinic receptor, it can cause either depolarization or hyperpolarization of the target cell depending on the specific variant of muscarinic receptor.