Final answer:
The number of neurotransmitter molecules that bind to the receptor and the duration of time they are bound to the receptor are determined by the specific receptor on the postsynaptic cell. When the neurotransmitter binds to the receptor, it changes the electrochemical potential of the target cell and triggers the next electrical impulse.
Step-by-step explanation:
The number of neurotransmitter molecules that bind to the receptor and the duration of time they are bound to the receptor are related to the specific receptor for the neurotransmitter on the postsynaptic cell. Receptors are specific for the neurotransmitter and the two fit together like a key and lock. When the neurotransmitter binds to the receptor on the surface of the postsynaptic cell, the electrochemical potential of the target cell changes, which ultimately launches the next electrical impulse.