Diffusion is the movement of molecules from and area of a. high to low concentration b. low to high concentration c. up to down concentration d. to the right

A is the correct answer

Neurotransmitters are messengers responsible for communication between neurons. they are released from synaptic vesicles and are received by receptors.  the communication is referred to as neurotransmission. the following statement is true about neurotransmitters: a. they're stored in synaptic vesicles in the axon.