How do varicosities differ from the synapses of skeletal and

How do varicosities differ from the synapses of skeletal and multiunit smooth muscle? What is the functional significance of this difference? (i.e. multiunit vs single unit smooth muscle)

Solution

Varicosities are points of contact with smooth muscle containing vesicles of neurotransmitter

Neurons make multiple synaptic contacts with the smooth muscles in form of swellings i.e varicosities

Single Unit smooth muscle In single unit smooth muscle the cells are connected by gap junctions and contract as a unit.

Multi unit smooth muscle In multiunit smooth muscles the cells are not coupled electrically; cells are stimulated and contract individually.Such an electrical isolation allows finer motor control