The ________ at the end of the axon branches contain small sacs called vesicles, which produce the neurotransmitters that are needed to allow impulse transmission to continue to the postsynaptic structures.

Fill in the blank(s) with the appropriate word(s).

synaptic knob

The synaptic knob contains vesicles that produce the neurotransmitters needed to allow impulse transmission to continue to postsynaptic structures such as dendrites, cell bodies, and axons of other neurons.