Final answer:
Ethanol acts as an agonist for GABA receptors in the brain, increasing the inhibitory effect of GABA neurotransmitter.
Step-by-step explanation:
Ethanol, the primary component of alcohol, acts as an agonist for GABA receptors in the brain.
GABA is a neurotransmitter that normally has an inhibitory effect on cells.
Ethanol and other psychoactive drugs that promote the activity of GABA receptors increase the inhibitory effect of GABA, resulting in the sedative and relaxing effects commonly associated with alcohol.