Answer
Smooth muscles are not always innervated. Skeletal muscles are always innervated. Smooth muscles receive innervation mainly from the autonomic nervous system,
Nerves to the smooth muscles do not have precis neuromuscular junctions.Instead, nerve fibers to smooth muscle have many swollen lumps along their lengths; these lumps are called varicosities. The varicosities (bumps) have vesicles that contain neurotransmitters (NT)--norepinephrine in the sympathetic system neurons and acetylcholine (ACH) in parasympathetic system neurons..
There are no motor endplates in myocyte arcolemman; instead the neurotransmitter receptors are spread all over the sarcolemma of myocytes. Excitation causes the the vesicles to release neurotransmitters into the tissue, benerally. As a consequence, each myocyte may respond to neurotransmitter released from more than one nerve fiber
Work Step by Step
There are no motor endplates in myocyte sarcolemma of smooth muscles; instead, the neurotransmitter receptors are spread all over the sarcolemma. Excitation causes the the vesicles to release neurotransmitters into the tissue, generally. As a consequence, each myocyte may respond to neurotransmitter released from more than one nerve fiber
Smooth muscle respond to a variety of stimuli , often without electrical stimulation
