Question

all of the following are typical characteristics of neurotransmitters except___
they are synthesized by a presynaptic neuron
they are released in response to stimulation
they are released into the bloodstream before reaching the postsynaptic c
they bind to specific receptors on the postsynaptic cell
they alter the physiology of the postsynaptic cell

Explanation:

Neurotransmitters are synthesized by presynaptic neurons, released in response to stimulation, bind to specific receptors on postsynaptic cells, and alter the physiology of postsynaptic cells. However, they are released into the synaptic cleft (not the bloodstream) to reach the postsynaptic cell.

Answer:

they are released into the bloodstream before reaching the postsynaptic cell