A barbiturate can be defined as a type of drug that acts as depressant and produce a variety of effects on the nervous system of an individual.
It can also act as a mild sedation for the death of the individual. Barbiturates blocks the nerves which blocks the sending and receiving of the signals.
It is used for the treatment of anxiety and insomnia but in a very small amount.
It is the rotation of the earth. when it rotates it causes a cycle of having the sun shine for some time, then the moon. hope this has helped, if did, plz mark as brainliest