your answer is b hope it helped
A neurotransmitter is to a key as a neural receptor site is to a lock.
Neurotransmitter is the chemical substance releases from the neurons for transmitting signals across the body. It is released at the synapse junction. There are 4 classes of neurotransmitters: amino acids, monoamines, peptides and purines. The examples include GABA, glutamate, serotonin, etc.
Neural receptor site is the location where neural receptors are found. These receptors may be found on the cell membrane, inside the cell or even outside the cells. A neurotransmitter binds to these receptors to make them active and functional. There are two types of receptors: Ionotropic receptors and Metabotropic receptors.
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