an enzyme known as acetylcholinesterase is present in the synaptic cleft. what is its role?

Brief Explanations:

Acetylcholinesterase is an enzyme. In the synaptic cleft, its key role is related to neurotransmitter - acetylcholine. After acetylcholine has transmitted the signal (by binding to receptors on the postsynaptic membrane), it needs to be removed to stop the continuous stimulation. Acetylcholinesterase catalyzes the breakdown of acetylcholine. This breakdown terminates the signal transmission at the synapse.

Answer:

It catalyzes the breakdown of acetylcholine, terminating its action as a neurotransmitter in the synaptic cleft.