Topic summary
Smooth muscle cell
Extracted from the Wikipedia article Smooth muscle.
Smooth muscle cells
A smooth-muscle cell is a spindle-shaped myocyte with a wide middle and tapering ends, and a single nucleus. Like striated muscle, smooth muscle can tense and relax. In the relaxed state, each cell is 30–200 micrometers in length, some thousands of times shorter than a skeletal muscle cell. There are no myofibrils present, but much of the cytoplasm is taken up by the proteins, myosin and actin, which together have the capability to contract.